CMP Journal 2025-06-11
Statistics
Nature: 23
Nature Materials: 1
Nature Nanotechnology: 1
Nature Physics: 1
Nature Reviews Physics: 1
Physical Review Letters: 12
Physical Review X: 2
arXiv: 71
Nature
SP140-RESIST pathway regulates interferon mRNA stability and antiviral immunity
Original Paper | Inflammation | 2025-06-10 20:00 EDT
Kristen C. Witt, Adam Dziulko, Joohyun An, Filip Pekovic, Arthur Xiuyuan Cheng, Grace Y. Liu, Ophelia Vosshall Lee, David J. Turner, Azra Lari, Moritz M. Gaidt, Roberto Chavez, Stefan A. Fattinger, Preethy Abraham, Harmandeep Dhaliwal, Angus Y. Lee, Dmitri I. Kotov, Laurent Coscoy, Britt A. Glaunsinger, Eugene Valkov, Edward B. Chuong, Russell E. Vance
Type I interferons are essential for antiviral immunity1 but must be tightly regulated2. The conserved transcriptional repressor SP140 inhibits interferon-β (Ifnb1) expression through an unknown mechanism3,4. Here we report that SP140 does not directly repress Ifnb1 transcription. Instead, SP140 negatively regulates Ifnb1 mRNA stability by directly repressing the expression of a previously uncharacterized regulator that we call RESIST (regulated stimulator of interferon via stabilization of transcript; previously annotated as annexin 2 receptor). RESIST promotes Ifnb1 mRNA stability by counteracting Ifnb1 mRNA destabilization mediated by the tristetraprolin (TTP) family of RNA-binding proteins and the CCR4-NOT deadenylase complex. SP140 localizes within punctate structures called nuclear bodies that have important roles in silencing DNA-virus gene expression in the nucleus3. Consistent with this observation, we find that SP140 inhibits replication of the gammaherpesvirus MHV68. The antiviral activity of SP140 is independent of its ability to regulate Ifnb1. Our results establish dual antiviral and interferon regulatory functions for SP140. We propose that SP140 and RESIST participate in antiviral effector-triggered immunity5,6.
Inflammation, Innate immunity
A neutral-atom Hubbard quantum simulator in the cryogenic regime
Original Paper | Magnetic properties and materials | 2025-06-10 20:00 EDT
Muqing Xu, Lev Haldar Kendrick, Anant Kale, Youqi Gang, Chunhan Feng, Shiwei Zhang, Aaron W. Young, Martin Lebrat, Markus Greiner
Ultracold fermionic atoms in optical lattices offer pristine realizations of Hubbard models1, which are fundamental to modern condensed-matter physics2,3. Despite notable advancements4,5,6, the accessible temperatures in these optical lattice material analogues are still too high to address many open problems7,8,9,10. Here we demonstrate a several-fold reduction in temperature6,11,12,13, bringing large-scale quantum simulations of the Hubbard model into an entirely new regime. This is accomplished by transforming a low-entropy product state into strongly correlated states of interest via dynamic control of the model parameters14,15, which is extremely challenging to simulate classically10. At half-filling, the long-range antiferromagnetic order is close to saturation, leading to a temperature of (T/t=0.0{5}_{-0.05}^{+0.06}) based on comparisons with numerically exact simulations. Doped away from half-filling, it is exceedingly challenging to realize systematically accurate and predictive numerical simulations9. Importantly, we are able to use quantum simulation to identify a new pathway for achieving similarly low temperatures with doping. This is confirmed by comparing short-range spin correlations to state-of-the-art, but approximate, constrained-path auxiliary-field quantum Monte Carlo simulations16,17,18. Compared with the cuprates2,19,20, the reported temperatures correspond to a reduction from far above to below room temperature, at which physics such as the pseudogap and stripe phases may be expected3,19,21,22,23,24. Our work opens the door to quantum simulations that solve open questions in material science, develop synergies with numerical methods and theoretical studies, and lead to discoveries of new physics8,10.
Magnetic properties and materials, Quantum simulation, Ultracold gases
A complementary two-dimensional material-based one instruction set computer
Original Paper | Electronic devices | 2025-06-10 20:00 EDT
Subir Ghosh, Yikai Zheng, Musaib Rafiq, Harikrishnan Ravichandran, Yongwen Sun, Chen Chen, Mrinmoy Goswami, Najam U Sakib, Muhtasim Ul Karim Sadaf, Andrew Pannone, Samriddha Ray, Joan M. Redwing, Yang Yang, Shubham Sahay, Saptarshi Das
Silicon has enabled advancements in semiconductor technology through miniaturization, but scaling challenges necessitate the exploration of new materials1. Two-dimensional (2D) materials, with their atomic thickness and high carrier mobility, offer a promising alternative2,3,4,5. Although significant progress has been made in wafer-scale growth6,7,8, high-performance field-effect transistors9,10,11,12,13,14,15,16,17,18,19,20 and circuits based on 2D materials21,22,23, achieving complementary metal-oxide-semiconductor (CMOS) integration remains a challenge. Here, we present a 2D one instruction set computer based on CMOS technology, leveraging the heterogeneous integration of large-area n-type MoS2 and p-type WSe2 field-effect transistors. By scaling the channel length, incorporating a high-κ gate dielectric and optimizing material growth and device postprocessing, we tailored the threshold voltages for both n- and p-type 2D field-effect transistors, achieving high drive currents and reduced subthreshold leakage. This enabled circuit operation below 3 V with an operating frequency of up to 25 kHz, which was constrained by parasitic capacitances, along with ultra-low power consumption in the picowatt range and a switching energy as low as approximately 100 pJ. Finally, we projected the performance of the one instruction set computer and benchmarked it against state-of-the-art silicon technology using an industry-standard SPICE-compatible BSIM-BULK model. This model was calibrated with experimental data that incorporate device-to-device variations. Although further advances are needed, this work marks a significant milestone in the application of 2D materials to microelectronics.
Electronic devices, Two-dimensional materials
Attosecond inner-shell lasing at ångström wavelengths
Original Paper | Free-electron lasers | 2025-06-10 20:00 EDT
Thomas M. Linker, Aliaksei Halavanau, Thomas Kroll, Andrei Benediktovitch, Yu Zhang, Yurina Michine, Stasis Chuchurka, Zain Abhari, Daniele Ronchetti, Thomas Fransson, Clemens Weninger, Franklin D. Fuller, Andy Aquila, Roberto Alonso-Mori, Sébastien Boutet, Marc W. Guetg, Agostino Marinelli, Alberto A. Lutman, Makina Yabashi, Ichiro Inoue, Taito Osaka, Jumpei Yamada, Yuichi Inubushi, Gota Yamaguchi, Toru Hara, Ganguli Babu, Devashish Salpekar, Farheen N. Sayed, Pulickel M. Ajayan, Jan Kern, Junko Yano, Vittal K. Yachandra, Matthias F. Kling, Claudio Pellegrini, Hitoki Yoneda, Nina Rohringer, Uwe Bergmann
Since the invention of the laser, nonlinear effects such as filamentation1, Rabi cycling2,3 and collective emission4 have been explored in the optical regime, leading to a wide range of scientific and industrial applications5,6,7,8. X-ray free-electron lasers (XFELs) have extended many optical techniques to X-rays for their advantages of ångström-scale spatial resolution and elemental specificity9. An example is XFEL-driven inner-shell Kα1 (2p3/2 → 1s1/2) X-ray lasing in elements ranging from neon to copper, which has been used for nonlinear spectroscopy and development of new X-ray laser sources10,11,12,13,14,15,16. Here we show that strong lasing effects similar to those in the optical regime can occur at 1.5-2.1 Å wavelengths during high-intensity (>1019 W cm-2) XFEL-driven Kα1 lasing of copper and manganese. Depending on the temporal XFEL pump pulse substructure, the resulting X-ray pulses (about 106-108 photons) can exhibit strong spatial inhomogeneities and spectral splitting, inhomogeneities and broadening. Three-dimensional Maxwell-Bloch calculations17 show that the observed spatial inhomogeneities result from X-ray filamentation and that the broad spectral features are driven by sub-femtosecond Rabi cycling. Our simulations indicate that these X-ray pulses can have pulse lengths of less than 100 attoseconds and coherence properties that provide opportunities for quantum X-ray optics applications.
Free-electron lasers, Ultrafast lasers
Glycosaminoglycan-driven lipoprotein uptake protects tumours from ferroptosis
Original Paper | Cancer metabolism | 2025-06-10 20:00 EDT
Dylan Calhoon, Lingjie Sang, Fubo Ji, Divya Bezwada, Sheng-Chieh Hsu, Feng Cai, Nathaniel Kim, Amrita Basu, Renfei Wu, Anastasia Pimentel, Bailey Brooks, Konnor La, Ana Paulina Serrano, Daniel L. Cassidy, Ling Cai, Vanina Toffessi-Tcheuyap, Maryam E. Moussa, Winnie Uritboonthai, Linh Truc Hoang, Meghana Kolli, Brooklyn Jackson, Vitaly Margulis, Gary Siuzdak, James Brugarolas, Ian Corbin, Derek A. Pratt, Ryan J. Weiss, Ralph J. DeBerardinis, Kıvanç Birsoy, Javier Garcia-Bermudez
Lipids are essential components of cancer cells due to their structural and signalling roles1. To meet metabolic demands, many cancers take up extracellular lipids2,3,4,5; however, how these lipids contribute to cancer growth and progression remains poorly understood. Here, using functional genetic screens, we identify uptake of lipoproteins–the primary mechanism for lipid transport in circulation–as a key determinant of ferroptosis sensitivity in cancer. Lipoprotein supplementation robustly inhibits ferroptosis across diverse cancer types, primarily through the delivery of α-tocopherol (α-toc), the most abundant form of vitamin E in human lipoproteins. Mechanistically, cancer cells take up lipoproteins through a pathway dependent on sulfated glycosaminoglycans (GAGs) linked to cell-surface proteoglycans. Disrupting GAG biosynthesis or acutely degrading surface GAGs reduces lipoprotein uptake, sensitizes cancer cells to ferroptosis and impairs tumour growth in mice. Notably, human clear cell renal cell carcinomas–a lipid-rich malignancy–exhibit elevated levels of chondroitin sulfate and increased lipoprotein-derived α-toc compared with normal kidney tissue. Together, our study establishes lipoprotein uptake as a critical anti-ferroptotic mechanism in cancer and implicates GAG biosynthesis as a therapeutic target.
Cancer metabolism, Cell death, Lipid peroxides, Lipoproteins
RIFINs displayed on malaria-infected erythrocytes bind KIR2DL1 and KIR2DS1
Original Paper | Immunology | 2025-06-10 20:00 EDT
Akihito Sakoguchi, Samuel G. Chamberlain, Alexander M. Mørch, Marcus Widdess, Thomas E. Harrison, Michael L. Dustin, Hisashi Arase, Matthew K. Higgins, Shiroh Iwanaga
Natural killer (NK) cells use inhibitory and activating immune receptors to differentiate between human cells and pathogens. Signalling by these receptors determines whether an NK cell becomes activated and destroys a target cell. In some cases, such as killer immunoglobulin-like receptors, immune receptors are found in pairs, with inhibitory and activating receptors containing nearly identical extracellular ligand-binding domains coupled to different intracellular signalling domains1. Previous studies showed that repetitive interspersed family (RIFIN) proteins, displayed on the surfaces of Plasmodium falciparum-infected erythrocytes, can bind to inhibitory immune receptors and dampen NK cell activation2,3, reducing parasite killing. However, no pathogen-derived ligand has been identified for any human activating receptor. Here we identified a clade of RIFINs that bind to inhibitory immune receptor KIR2DL1 more strongly than KIR2DL1 binds to the human ligand (MHC class I). This interaction mediates inhibitory signalling and suppresses the activation of KIR2DL1-expressing NK cells. We show that KIR2DL1-binding RIFINs are abundant in field-isolated strains from both Africa and Asia and reveal how the two RIFINs bind to KIR2DL1. The RIFIN binding surface of KIR2DL1 is conserved in the cognate activating immune receptor KIR2DS1. We find that KIR2DL1-binding RIFINs can also bind to KIR2DS1, resulting in the activation of KIR2DS1-expressing NK cells. This study demonstrates that activating killer immunoglobulin-like receptors can recruit NK cells to target a pathogen and reveals a potential role for activating immune receptors in controlling malaria infection.
Immunology, Parasite immune evasion
Developmental trajectory and evolutionary origin of thymic mimetic cells
Original Paper | Adaptive immunity | 2025-06-10 20:00 EDT
Anja Nusser, Oliver S. Thomas, Gaoqun Zhang, Daisuke Nagakubo, Laura Arrigoni, Brigitte Krauth, Thomas Boehm
The generation of self-tolerant repertoires of T cells depends on the expression of peripheral self antigens in the thymic epithelium1 and the presence of small populations of cells that mimic the diverse phenotypes of peripheral tissues2,3,4,5,6,7. Whereas the molecular underpinnings of self-antigen expression have been extensively studied8, the developmental origins and differentiation pathways of thymic mimetic cells remain to be identified. Moreover, the histological identification of myoid and other peripheral cell types as components of the thymic microenvironment of many vertebrate species9 raises questions regarding the evolutionary origin of this unique tolerance mechanism. Here we show that during mouse development, mimetic cells appear in the microenvironment in two successive waves. Cells that exhibit transcriptional signatures characteristic of muscle, ionocyte, goblet and ciliated cells emerge before birth, whereas others, such as those that mimic enterohepatic cells and skin keratinocytes, appear postnatally. These two groups also respond differently to modulations of thymic epithelial cell progenitor pools caused by deletions of Foxn1 and Ascl1, expression of a hypomorphic variant of the transcription factor FOXN1, and overexpression of the signalling molecules BMP4 and FGF7. Differences in mimetic cell populations were also observed in thymic microenvironments reconstructed by replacement of mouse Foxn1 with evolutionarily ancient Foxn1/4 gene family members, including the Foxn4 gene of the cephalochordate amphioxus and the Foxn4 and Foxn1 genes of a cartilaginous fish. Whereas some cell types, such as ciliated cells, develop in the thymus in the absence of FOXN1, mimetic cells that appear postnatally, such as enterohepatic cells, require the activity of the vertebrate-specific transcription factor FOXN1. The thymus of cartilaginous fishes and the thymoid of lampreys, a representative of jawless vertebrates, which exhibit an alternative adaptive immune system10, also harbour cells that express genes encoding peripheral tissue components such as the liver-specific protein transthyretin. Our findings suggest an evolutionary model of successive changes of thymic epithelial genetic networks enabling the coordinated contribution of peripheral antigen expression and mimetic cell formation to achieve central tolerance for vertebrate-specific innovations of tissues such as the liver11,12.
Adaptive immunity, Immunology, Lymphoid tissues
Preparation of a neutral nitrogen allotrope hexanitrogen C2h-N6
Original Paper | Chemical bonding | 2025-06-10 20:00 EDT
Weiyu Qian, Artur Mardyukov, Peter R. Schreiner
Compounds consisting only of the element nitrogen (polynitrogens or nitrogen allotropes) are considered promising clean energy-storage materials owing to their immense energy content that is much higher than hydrogen, ammonia or hydrazine, which are in common use, and because they release only harmless nitrogen on decomposition1. However, their extreme instability poses a substantial synthetic challenge and no neutral molecular nitrogen allotrope beyond N2 has been isolated2,3. Here we present the room-temperature preparation of molecular N6 (hexanitrogen) through the gas-phase reaction of chlorine or bromine with silver azide, followed by trapping in argon matrices at 10 K. We also prepared neat N6 as a film at liquid nitrogen temperature (77 K), further indicating its stability. Infrared and ultraviolet-visible (UV-Vis) spectroscopy, 15N-isotope labelling and ab initio computations firmly support our findings. The preparation of a metastable molecular nitrogen allotrope beyond N2 contributes to our fundamental scientific knowledge and possibly opens new opportunities for future energy-storage concepts.
Chemical bonding, Materials chemistry, Chemical synthesis
Probing phonon transport dynamics across an interface by electron microscopy
Original Paper | Atomistic models | 2025-06-10 20:00 EDT
Fachen Liu, Ruilin Mao, Zhiqiang Liu, Jinlong Du, Peng Gao
Understanding thermal transport mechanisms across material interfaces is crucial for advancing semiconductor technologies, particularly in miniaturized devices operating under extreme power densities1,2. Although the interface phonon-mediated processes are theoretically established3,4,5,6 as the dominant mechanism for interfacial thermal transport in semiconductors7, their nanoscale dynamics remain experimentally elusive owing to challenges in measuring the temperature and non-equilibrium phonon distributions across the buried interface8,9,10,11. Here we overcome these limitations by using in situ vibrational electron energy-loss spectroscopy (EELS) in an electron microscope to nanoscale profile temperature gradients across the AlN-SiC interface during thermal transport and map its non-equilibrium phonon occupations at sub-nanometre resolution. We observe a sharp temperature drop within about 2 nm across the interface, enabling direct extraction of relative interfacial thermal resistance (ITR). During thermal transport, the mismatch of phonon modes’ thermal conductivity at the interface causes substantial non-equilibrium phonons nearby, making the populations of interface modes different under forward and reverse heat flow and also leading to marked changes in the modal temperature of AlN optical phonons within about 3 nm of the interface. These results reveal the phonon transport dynamics at the (sub-)nanoscale and establish the inelastic phonon scattering mechanism involved by interface modes, offering valuable insights into the engineering of thermal interfaces.
Atomistic models, Characterization and analytical techniques, Semiconductors, Surfaces, interfaces and thin films, Transmission electron microscopy
Molecular hydrogen in the extremely metal- and dust-poor galaxy Leo P
Original Paper | Galaxies and clusters | 2025-06-10 20:00 EDT
O. Grace Telford, Karin M. Sandstrom, Kristen B. W. McQuinn, Simon C. O. Glover, Elizabeth J. Tarantino, Alberto D. Bolatto, Ryan J. Rickards Vaught
The James Webb Space Telescope (JWST) has revealed unexpectedly rapid galaxy assembly in the early Universe, in tension with galaxy-formation models1,2,3. At the low abundances of heavy elements (metals) and dust typical in early galaxies, the formation of molecular hydrogen and its connection to star formation remain poorly understood. Some models predict that stars form in predominantly atomic gas at low metallicity4,5, in contrast to molecular gas at higher metallicities6. Despite repeated searches7, cold molecular gas has not yet been observed in any galaxy below 7% solar metallicity8. Here we report the detection of rotational emission from molecular hydrogen near the only O-type star in the 3% solar metallicity galaxy Leo P (refs. 9,10) with JWST’s Mid-Infrared Instrument/Medium Resolution Spectroscopy (MIRI-MRS) observing mode. These observations place a lower limit on Leo P’s molecular gas content, and modelling of the photodissociation region illuminated by the O star suggests a compact (≤2.6 pc radius), approximately 104 M⊙ cloud. We also report a stringent upper limit on carbon monoxide (CO) emission from a deep search with the Atacama Large Millimeter/submillimeter Array (ALMA). Our results highlight the power of MIRI-MRS to characterize even small ultraviolet-illuminated molecular clouds in the low-metallicity regime, in which the traditional observational tracer CO is uninformative. This discovery pushes the limiting metallicity at which molecular gas is present in detectable quantities more than a factor of two lower, providing crucial empirical guidance for models of the interstellar medium in early galaxies.
Galaxies and clusters, Interstellar medium
Traceable random numbers from a non-local quantum advantage
Original Paper | Information theory and computation | 2025-06-10 20:00 EDT
Gautam A. Kavuri, Jasper Palfree, Dileep V. Reddy, Yanbao Zhang, Joshua C. Bienfang, Michael D. Mazurek, Mohammad A. Alhejji, Aliza U. Siddiqui, Joseph M. Cavanagh, Aagam Dalal, Carlos Abellán, Waldimar Amaya, Morgan W. Mitchell, Katherine E. Stange, Paul D. Beale, Luís T. A. N. Brandão, Harold Booth, René Peralta, Sae Woo Nam, Richard P. Mirin, Martin J. Stevens, Emanuel Knill, Lynden K. Shalm
The unpredictability of random numbers is fundamental to both digital security1,2 and applications that fairly distribute resources3,4. However, existing random number generators have limitations–the generation processes cannot be fully traced, audited and certified to be unpredictable. The algorithmic steps used in pseudorandom number generators5 are auditable, but they cannot guarantee that their outputs were a priori unpredictable given knowledge of the initial seed. Device-independent quantum random number generators6,7,8,9 can ensure that the source of randomness was unknown beforehand, but the steps used to extract the randomness are vulnerable to tampering. Here we demonstrate a fully traceable random number generation protocol based on device-independent techniques. Our protocol extracts randomness from unpredictable non-local quantum correlations, and uses distributed intertwined hash chains to cryptographically trace and verify the extraction process. This protocol forms the basis for a public traceable and certifiable quantum randomness beacon that we have launched10. Over the first 40 days of operation, we completed the protocol 7,434 out of 7,454 attempts–a success rate of 99.7%. Each time the protocol succeeded, the beacon emitted a pulse of 512 bits of traceable randomness. The bits are certified to be uniform with error multiplied by actual success probability bounded by 2-64. The generation of certifiable and traceable randomness represents a public service that operates with an entanglement-derived advantage over comparable classical approaches.
Information theory and computation, Quantum information, Quantum optics
Weakly space-confined all-inorganic perovskites for light-emitting diodes
Original Paper | Inorganic LEDs | 2025-06-10 20:00 EDT
Chenchen Peng, Haitao Yao, Othman Ali, Wenjing Chen, Yingguo Yang, Zongming Huang, Hui Liu, Jianyu Li, Tao Chen, Zhijian Li, Mei Sun, Hongmin Zhou, Xiangru Tao, Nana Wang, Jianpu Wang, Zhengguo Xiao
Metal halide perovskites are promising materials for light-emitting diodes (LEDs)1,2,3,4. Spatially confining charge carriers using nanocrystal/quantum dots5,6,7,8,9, low-dimensional perovskites10,11,12,13 and ultrathin perovskite layers14 have all been used to improve the external quantum efficiency of perovskite LEDs (PeLEDs). However, most strongly space-confined perovskites suffer from severe Auger recombination, ion migration and thermal instability, resulting in limited brightness and operational lifetime6,7,10,11,12,14,15,16,17. Here, we report an alternative strategy based on weakly space-confined, large-grained crystals of all-inorganic perovskite. Sacrificial additives, namely, hypophosphorous acid and ammonium chloride, were used to induce nucleation and crystallization of caesium lead bromide, resulting in monocrystal grains with minimized trap density and a high photoluminescence quantum yield. Benefiting from the high carrier mobility and suppressed Auger recombination, we obtained efficient PeLEDs with an external quantum efficiency reaching 22.0%, which remained above 20% at a high current density near 1,000 mA cm-2 and a brightness of over 1,167,000 cd m-2. Furthermore, benefiting from the suppressed ion migration and better thermal stability, the extrapolated half-lifetime of the weakly space-confined PeLEDs increased to 185,600 h under an initial luminance of 100 cd m-2 at room temperature. Our work is a new approach for designing efficient, bright and stable PeLEDs for real applications.
Inorganic LEDs
Abyssal seafloor as a key driver of ocean trace-metal biogeochemical cycles
Original Paper | Element cycles | 2025-06-10 20:00 EDT
Jianghui Du, Brian A. Haley, James McManus, Patrick Blaser, Jörg Rickli, Derek Vance
Trace elements and isotopes (TEIs) are important to marine life and are essential tools for studying ocean processes1. Two different frameworks have arisen regarding marine TEI cycling: reversible scavenging favours water-column control on TEI distributions2,3,4,5, and seafloor boundary exchange emphasizes sedimentary imprints on water-column biogeochemistry6,7. These two views lead to disparate interpretations of TEI behaviours8,9,10. Here we use rare earth elements and neodymium isotopes as exemplar tracers of particle scavenging11 and boundary exchange6,7,12. We integrate these data with models of particle cycling and sediment diagenesis to propose a general framework for marine TEI cycling. We show that, for elements with greater affinity for manganese oxide than biogenic particles, scavenging is a net sink throughout the water column, contrary to a common assumption for reversible scavenging3,13. In this case, a benthic flux supports increasing elemental concentrations with water depth. This sedimentary source consists of two components: one recycled from elements scavenged by water-column particles, and another newly introduced to the water column through marine silicate weathering inside sediment8,14,15. Abyssal oxic diagenesis drives this benthic source, and exerts a strong influence on water-column biogeochemistry through seafloor geometry and bottom-intensified turbulent mixing16,17. Our findings affirm the role of authigenic minerals, often overshadowed by biogenic particles, in water-column cycling18, and suggest that the abyssal seafloor, often regarded as inactive, is a focus of biogeochemical transformation19,20.
Element cycles, Marine chemistry
A new Mongolian tyrannosauroid and the evolution of Eutyrannosauria
Original Paper | Palaeoecology | 2025-06-10 20:00 EDT
Jared T. Voris, Darla K. Zelenitsky, Yoshitsugu Kobayashi, Sean P. Modesto, François Therrien, Hiroki Tsutsumi, Tsogtbaatar Chinzorig, Khishigjav Tsogtbaatar
Eutyrannosaurians were large predatory dinosaurs that dominated Asian and North American terrestrial faunas in latest Cretaceous times. These apex predators arose from smaller-bodied tyrannosauroids during the ‘middle’ Cretaceous that are poorly known owing to the paucity of fossil material1,2,3. Here we report on a new tyrannosauroid, Khankhuuluu mongoliensis gen. et sp. nov., from lower Upper Cretaceous deposits of Mongolia that provides a new perspective on eutyrannosaurian origins and evolution. Phylogenetic analyses recover Khankhuuluu immediately outside Eutyrannosauria and recover the massive, deep-snouted Tyrannosaurini and the smaller, gracile, shallow-snouted Alioramini as highly derived eutyrannosaurian sister clades. Khankhuuluu and the late-diverging Alioramini independently share features related to a shallow skull and gracile build with juvenile eutyrannosaurians, reinforcing the key role heterochrony had in eutyrannosaurian evolution. Although eutyrannosaurians were mainly influenced by peramorphosis or accelerated growth4,5,6,7,8,9,10, Alioramini is revealed as a derived lineage that retained immature features through paedomorphosis and is not a more basal lineage as widely accepted11,12,13,14,15,16,17,18,19. Our results reveal that Asian tyrannosauroids (similar to Khankhuuluu) dispersed to North America, giving rise to Eutyrannosauria in the mid-Late Cretaceous. Eutyrannosauria diversified and remained exclusively in North America until a single dispersal to Asia in the latest Cretaceous that established Alioramini and Tyrannosaurini. Stark morphological differences between Alioramini and Tyrannosaurini probably evolved due to divergent heterochronic trends–paedomorphosis versus peramorphosis, respectively–allowing them to coexist in Asia and occupy different ecological niches.
Palaeoecology, Palaeontology, Phylogenetics, Taxonomy
Brain implantation of soft bioelectronics via embryonic development
Original Paper | Bionanoelectronics | 2025-06-10 20:00 EDT
Hao Sheng, Ren Liu, Qiang Li, Zuwan Lin, Yichun He, Thomas S. Blum, Hao Zhao, Xin Tang, Wenbo Wang, Lishuai Jin, Zheliang Wang, Emma Hsiao, Paul Le Floch, Hao Shen, Ariel J. Lee, Rachael Alice Jonas-Closs, James Briggs, Siyi Liu, Daniel Solomon, Xiao Wang, Jessica L. Whited, Nanshu Lu, Jia Liu
Developing bioelectronics capable of stably tracking brain-wide, single-cell, millisecond-resolved neural activity in the developing brain is critical for advancing neuroscience and understanding neurodevelopmental disorders. During development, the three-dimensional structure of the vertebrate brain arises from a two-dimensional neural plate1,2. These large morphological changes have previously posed a challenge for implantable bioelectronics to reliably track neural activity throughout brain development3,4,5,6,7,8,9. Here we introduce a tissue-level-soft, submicrometre-thick mesh microelectrode array that integrates into the embryonic neural plate by leveraging the tissue’s natural two-dimensional-to-three-dimensional reconfiguration. As organogenesis progresses, the mesh deforms, stretches and distributes throughout the brain, seamlessly integrating with neural tissue. Immunostaining, gene expression analysis and behavioural testing confirm no adverse effects on brain development or function. This embedded electrode array enables long-term, stable mapping of how single-neuron activity and population dynamics emerge and evolve during brain development. In axolotl models, it not only records neural electrical activity during regeneration but also modulates the process through electrical stimulation.
Bionanoelectronics, Sensors and biosensors
Physical restoration of a painting with a digitally constructed mask
Original Paper | Arts | 2025-06-10 20:00 EDT
Alex Kachkine
Conservation of damaged oil paintings requires manual inpainting of losses1,2, leading to months-long treatments of considerable expense; 70% of paintings in institutional collections are locked away from public view, in part because of treatment cost3,4. Recent advancements in digital image reconstruction have helped to envision treatment results, although without any direct means of achieving them5,6,7,8. Here I describe the physically applied digital restoration of a painting, a highly damaged oil-on-panel attributed to the Master of the Prado Adoration from the late fifteenth century. In parallel, 5,612 losses spanning 66,205 mm2 and 57,314 colours were infilled with a reversible laminate mask comprising a colour-accurate bilayer of printed pigments on polymeric films. To ensure the effectiveness of the restoration, ethical principles in painting conservation were implemented quantitatively for digital mask construction, a critically important foundation lacking in the current digital restoration literature. The infill process took 3.5 h, an estimated 66 times faster than conventional inpainting, and the result closely matched the simulation. This approach grants greatly increased foresight and flexibility to conservators, enabling the restoration of countless damaged paintings deemed unworthy of high conservation budgets.
Arts, Computational science, Design, synthesis and processing, Mechanical engineering
Dynamic assemblies and coordinated reactions of non-homologous end joining
Original Paper | Electron microscopy | 2025-06-10 20:00 EDT
Lan Liu, Jun Li, Metztli Cisneros-Aguirre, Arianna Merkell, Jeremy M. Stark, Martin Gellert, Wei Yang
Non-homologous end joining (NHEJ) is the main repair pathway of double-strand DNA breaks in higher eukaryotes1,2. Here we report reconstitution of the final steps of NHEJ and structures of DNA polymerase μ and ligase IV (LIG4) engaged in gap filling and end joining. These reactions take place in a flexible ω-shaped framework composed of XRCC4 and XLF. Two broken DNA ends, each encircled by Ku70-Ku80 internally, are docked onto the ω frame, mediated by LIG4. DNA polymerase and ligase attached to each ω arm repair only one broken strand of a defined polarity; the final steps of NHEJ requires coordination and toggling of a pair of such enzymes. The facilitators XLF and PAXX additively stimulate NHEJ reactions. As DNA-end sensor and protector, LIG4 replaces DNA-PKcs for end joining and bridges the two DNA ends for polymerase to fill remaining gaps. These assemblies present new targets for NHEJ inhibition to enhance efficacy of radiotherapy and accuracy of gene editing.
Electron microscopy, Enzyme mechanisms, Non-homologous-end joining
Metabolic adaptations direct cell fate during tissue regeneration
Original Paper | Energy metabolism | 2025-06-10 20:00 EDT
Almudena Chaves-Perez, Scott E. Millman, Sudha Janaki-Raman, Yu-Jui Ho, Clemens Hinterleitner, Valentin J. A. Barthet, John P. Morris IV, Francisco M. Barriga, Jose Reyes, Aye Kyaw, H. Amalia Pasolli, Dana Pe’er, Craig B. Thompson, Lydia W. S. Finley, Justin R. Cross, Scott W. Lowe
Although cell-fate specification is generally attributed to transcriptional regulation, emerging data also indicate a role for molecules linked with intermediary metabolism. For example, α-ketoglutarate (αKG), which fuels energy production and biosynthetic pathways in the tricarboxylic acid (TCA) cycle, is also a co-factor for chromatin-modifying enzymes1,2,3. Nevertheless, whether TCA-cycle metabolites regulate cell fate during tissue homeostasis and regeneration remains unclear. Here we show that TCA-cycle enzymes are expressed in the intestine in a heterogeneous manner, with components of the αKG dehydrogenase complex4,5,6 upregulated in the absorptive lineage and downregulated in the secretory lineage. Using genetically modified mouse models and organoids, we reveal that 2-oxoglutarate dehydrogenase (OGDH), the enzymatic subunit of the αKG dehydrogenase complex, has a dual, lineage-specific role. In the absorptive lineage, OGDH is upregulated by HNF4 transcription factors to maintain the bioenergetic and biosynthetic needs of enterocytes. In the secretory lineage, OGDH is downregulated through a process that, when modelled, increases the levels of αKG and stimulates the differentiation of secretory cells. Consistent with this, in mouse models of colitis with impaired differentiation and maturation of secretory cells, inhibition of OGDH or supplementation with αKG reversed these impairments and promoted tissue healing. Hence, OGDH dependency is lineage-specific, and its regulation helps to direct cell fate, offering insights for targeted therapies in regenerative medicine.
Energy metabolism, Intestinal stem cells, Stem-cell differentiation, Ulcerative colitis
Targeting GRPR for sex hormone-dependent cancer after loss of E-cadherin
Original Paper | Melanoma | 2025-06-10 20:00 EDT
Jérémy H. Raymond, Zackie Aktary, Marie Pouteaux, Valérie Petit, Flavie Luciani, Maria Wehbe, Patrick Gizzi, Claire Bourban, Didier Decaudin, Fariba Nemati, Igor Martianov, Irwin Davidson, Catherine-Laure Tomasetto, Richard M. White, Florence Mahuteau-Betzer, Béatrice Vergier, Lionel Larue, Véronique Delmas
Sex inequalities in cancer are well documented, but the current limited understanding is hindering advances in precision medicine and therapies1. Consideration of ethnicity, age and sex is essential for the management of cancer patients because they underlie important differences in both incidence and response to treatment2,3. Age-related hormone production, which is a consistent divergence between the sexes, is underestimated in cancers that are not recognized as being hormone dependent4,5,6. Here, we show that premenopausal women have increased vulnerability to cancers, and we identify the cell-cell adhesion molecule E-cadherin as a crucial component in the oestrogen response in various cancers, including melanoma. In a mouse model of melanoma, we discovered an oestrogen-sensitizing pathway connecting E-cadherin, β-catenin, oestrogen receptor-α and GRPR that promotes melanoma aggressiveness in women. Inhibiting this pathway by targeting GRPR or oestrogen receptor-α reduces metastasis in mice, indicating its therapeutic potential. Our study introduces a concept linking hormone sensitivity and tumour phenotype in which hormones affect cell phenotype and aggressiveness. We have identified an integrated pro-tumour pathway in women and propose that targeting a G-protein-coupled receptor with drugs not commonly used for cancer treatment could be more effective in treating E-cadherin-dependent cancers in women. This study emphasizes the importance of sex-specific factors in cancer management and offers hope of improving outcomes in various cancers.
Melanoma, Transcription
Discovery of FoTO1 and Taxol genes enables biosynthesis of baccatin III
Original Paper | Enzymes | 2025-06-10 20:00 EDT
Conor James McClune, Jack Chun-Ting Liu, Chloe Wick, Ricardo De La Peña, Bernd Markus Lange, Polly M. Fordyce, Elizabeth S. Sattely
Plants make complex and potent therapeutic molecules1,2, but sourcing these molecules from natural producers or through chemical synthesis is difficult, which limits their use in the clinic. A prominent example is the anti-cancer therapeutic paclitaxel (sold under the brand name Taxol), which is derived from yew trees (Taxus species)3. Identifying the full paclitaxel biosynthetic pathway would enable heterologous production of the drug, but this has yet to be achieved despite half a century of research4. Within Taxus‘ large, enzyme-rich genome5, we suspected that the paclitaxel pathway would be difficult to resolve using conventional RNA-sequencing and co-expression analyses. Here, to improve the resolution of transcriptional analysis for pathway identification, we developed a strategy we term multiplexed perturbation × single nuclei (mpXsn) to transcriptionally profile cell states spanning tissues, cell types, developmental stages and elicitation conditions. Our data show that paclitaxel biosynthetic genes segregate into distinct expression modules that suggest consecutive subpathways. These modules resolved seven new genes, allowing a de novo 17-gene biosynthesis and isolation of baccatin III, the industrial precursor to Taxol, in Nicotiana benthamiana leaves, at levels comparable with the natural abundance in Taxus needles. Notably, we found that a nuclear transport factor 2 (NTF2)-like protein, FoTO1, is crucial for promoting the formation of the desired product during the first oxidation, resolving a long-standing bottleneck in paclitaxel pathway reconstitution. Together with a new β-phenylalanine-CoA ligase, the eight genes discovered here enable the de novo biosynthesis of 3’-N-debenzoyl-2’-deoxypaclitaxel. More broadly, we establish a generalizable approach to efficiently scale the power of co-expression analysis to match the complexity of large, uncharacterized genomes, facilitating the discovery of high-value gene sets.
Enzymes, Gene expression analysis, Secondary metabolism
Rapid emergence of a maths gender gap in first grade
Original Paper | Education | 2025-06-10 20:00 EDT
P. Martinot, B. Colnet, T. Breda, J. Sultan, L. Touitou, P. Huguet, E. Spelke, G. Dehaene-Lambertz, P. Bressoux, S. Dehaene
Preventing gender disparities in mathematics is a worldwide preoccupation1,2. In infancy and early childhood, boys and girls exhibit similar core knowledge of number and space3,4,5,6,7,8. Gender disparities in maths are, therefore, thought to primarily reflect an internalization of the sociocultural stereotype that ‘girls are bad at maths’. However, where, when and how widely this stereotype becomes entrenched remains uncertain. Here, we report the results of a 4-year longitudinal assessment of language and mathematical performance of all French first and second graders (2,653,082 children). Boys and girls exhibited very similar maths scores upon school entry, but a gender gap in favour of boys became highly significant after 4 months of schooling and reached an effect size of about 0.20 after 1 year. These findings were repeated each year and varied only slightly across family, class or school type and socio-economic level. Although schooling correlated with age, exploiting the near-orthogonal variations indicated that the gender gap increased with schooling rather than with age. These findings point to the first year of school as the time and place where a maths gender gap emerges in favour of boys, thus helping focus the search for solutions and interventions.
Education, Human behaviour, Social behaviour
A fully open AI foundation model applied to chest radiography
Original Paper | Biomedical engineering | 2025-06-10 20:00 EDT
DongAo Ma, Jiaxuan Pang, Michael B. Gotway, Jianming Liang
Chest radiography frequently serves as baseline imaging for most lung diseases1. Deep learning has great potential for automating the interpretation of chest radiography2. However, existing chest radiographic deep learning models are limited in diagnostic scope, generalizability, adaptability, robustness and extensibility. To overcome these limitations, we have developed Ark+, a foundation model applied to chest radiography and pretrained by cyclically accruing and reusing the knowledge from heterogeneous expert labels in numerous datasets. Ark+ excels in diagnosing thoracic diseases. It expands the diagnostic scope and addresses potential misdiagnosis. It can adapt to evolving diagnostic needs and respond to novel diseases. It can learn rare conditions from a few samples and transfer to new diagnostic settings without training. It tolerates data biases and long-tailed distributions, and it supports federated learning to preserve privacy. All codes and pretrained models have been released, so that Ark+ is open for fine-tuning, local adaptation and improvement. It is extensible to several modalities. Thus, it is a foundation model for medical imaging. The exceptional capabilities of Ark+ stem from our insight: aggregating various datasets diversifies the patient populations and accrues knowledge from many experts to yield unprecedented performance while reducing annotation costs3. The development of Ark+ reveals that open models trained by accruing and reusing knowledge from heterogeneous expert annotations with a multitude of public (big or small) datasets can surpass the performance of proprietary models trained on large data. We hope that our findings will inspire more researchers to share code and datasets or federate privacy-preserving data to create open foundation models with diverse, global expertise and patient populations, thus accelerating open science and democratizing AI for medicine.
Biomedical engineering, Computer science, Image processing, Machine learning
Early life high fructose impairs microglial phagocytosis and neurodevelopment
Original Paper | Apoptosis | 2025-06-10 20:00 EDT
Zhaoquan Wang, Allie Lipshutz, Celia Martínez de la Torre, Alissa J. Trzeciak, Zong-Lin Liu, Isabella C. Miranda, Tomi Lazarov, Ana C. Codo, Jesús E. Romero-Pichardo, Achuth Nair, Tanya Schild, Waleska Saitz Rojas, Pedro H. V. Saavedra, Ann K. Baako, Kelvin Fadojutimi, Michael S. Downey, Frederic Geissmann, Giuseppe Faraco, Li Gan, Jon Iker Etchegaray, Christopher D. Lucas, Marina Tanasova, Christopher N. Parkhurst, Melody Y. Zeng, Kayvan R. Keshari, Justin S. A. Perry
Despite the success of fructose as a low-cost food additive, epidemiological evidence suggests that high fructose consumption during pregnancy or adolescence is associated with disrupted neurodevelopment1,2,3. An essential step in appropriate mammalian neurodevelopment is the phagocytic elimination of newly formed neurons by microglia, the resident professional phagocyte of the central nervous system4. Whether high fructose consumption in early life affects microglial phagocytosis and whether this directly affects neurodevelopment remains unknown. Here we show that offspring born to female mice fed a high-fructose diet and neonates exposed to high fructose exhibit decreased phagocytic activity in vivo. Notably, deletion of the high-affinity fructose transporter GLUT5 (also known as SLC2A5) in neonatal microglia completely reversed microglia phagocytic dysfunction, suggesting that high fructose directly affects neonatal development by suppressing microglial phagocytosis. Mechanistically, we found that high-fructose treatment of mouse and human microglia suppresses phagocytosis capacity, which is rescued in GLUT5-deficient microglia. Additionally, we found that high fructose drives significant GLUT5-dependent fructose uptake and catabolism to fructose 6-phosphate, rewiring microglial metabolism towards a hypo-phagocytic state in part by enforcing mitochondrial localization of the enzyme hexokinase 2. Mice exposed to high fructose as neonates develop anxiety-like behaviour as adolescents–an effect that is rescued in GLUT5-deficient mice. Our findings provide a mechanistic explanation for the epidemiological observation that high-fructose exposure during early life is associated with increased prevalence of adolescent anxiety disorders.
Apoptosis, Dietary carbohydrates, Microglia, Neuroimmunology
Nature Materials
Resonant osmotic diodes for voltage-induced water filtration across composite membranes
Original Paper | Fluid dynamics | 2025-06-10 20:00 EDT
Soufiane Abdelghani-Idrissi, Lucie Ries, Geoffrey Monet, Javier Perez-Carvajal, Zacharie Pilo, Paulina Sarnikowski, Alessandro Siria, Lydéric Bocquet
Nanofluidics have led to the discovery of unconventional properties for water and ion transport at the nanoscale, but key challenges remain in their large-scale implementation. Here we report an osmotic resonance across macroscopic composite membranes made by the assembly of microporous and mesoporous layers, taking root from the rectified osmotic transport in nanopores. This osmotic diode induces ionic sieving and continuous fast macroscopic electro-osmotic transport. This is the basis for a versatile approach for water purification, by which fresh water is driven across a composite material under an a.c. electric field. Water flow is driven within the mesoporous layer, while selectivity is achieved within the microporous layer. The maximal rectified, diode-like water flow is found to be in the hertz range. Building on analytical predictions, we show that a conversion factor of up to ~15 equivalent bars per applied volt can be reached using appropriate materials.
Fluid dynamics, Porous materials, Two-dimensional materials
Nature Nanotechnology
Polymeric stabilization at the gas-liquid interface for durable solar hydrogen production from plastic waste
Original Paper | Devices for energy harvesting | 2025-06-10 20:00 EDT
Wang Hee Lee, Hyunseo Park, Chan Woo Lee, Haeseong Kim, Jae Hwan Jeong, Jeong In Yun, Seong-Uk Bang, Junhyeok Heo, Kyung Hyun Ahn, Gi Doo Cha, Megalamane S. Bootharaju, Byoung-Hoon Lee, Jaeyune Ryu, Minho Kim, Taeghwan Hyeon, Dae-Hyeong Kim
Heterogeneous photocatalysis offers substantial potential for sustainable energy conversion, yet its industrial application is constrained by limited durability under stringent photochemical conditions. Achieving high photocatalytic activity often requires harsh reaction conditions, compromising catalyst stability and longevity. Here we propose a strategy involving polymeric stabilization of photocatalytic centres uniquely localized at the gas-liquid interface, substantially enhancing both the catalytic activity and stability. Applied to the photocatalytic conversion of plastic waste into solar hydrogen, this approach maintained its catalytic performance over 2 months under harsh conditions. Using 0.3 wt% dynamically stabilized atomic Pt/TiO2 photocatalysts and concentrated sunlight, we achieved a plastic reforming activity of 271 mmolH2 h-1 m-2. Scaling to 1 m2 under natural sunlight yielded a hydrogen production rate of 0.906 l per day from polyethylene terephthalate waste. Economic analysis and extensive-scale simulations suggest this strategy as a promising pathway for high-performance, durable photocatalysis, advancing renewable energy conversion.
Devices for energy harvesting, Nanocomposites, Photocatalysis
Nature Physics
Ultrasensitive single-ion electrometry in a magnetic field gradient
Original Paper | Atomic and molecular physics | 2025-06-10 20:00 EDT
F. Bonus, C. Knapp, C. H. Valahu, M. Mironiuc, S. Weidt, W. K. Hensinger
Hyperfine energy levels in trapped ions offer long-lived spin states. In addition, the motion of these charged particles couples strongly to electric field perturbations. These characteristics make trapped ions attractive platforms for the quantum sensing of electric fields. However, the spin states do not exhibit a strong intrinsic coupling to electric fields, lim iting the achievable sensitivity. Here, we amplify the coupling between electric field perturbations and the spin states by using a static magnetic field gradient. Displacements of the trapped ion resulting from the applied electric field perturbations are thereby mapped to an instantaneous change in the energy-level splitting of the internal spin states. This gradient-mediated coupling of the electric field to the spin enables the use of well-established magnetometry protocols for electrometry, making it possible to achieve extremely sensitive measurements of d.c. and a.c. electric fields. We also employ a rotating-frame relaxometry technique and demonstrate the use of our quantum sensor as an electric field noise spectrum analyser. Finally, we describe a set of hardware modifications that are capable of achieving a further improvement in sensitivity by up to six orders of magnitude.
Atomic and molecular physics, Quantum mechanics, Quantum metrology, Quantum physics
Nature Reviews Physics
Accelerating fusion research via supercomputing
Review Paper | Computational science | 2025-06-10 20:00 EDT
Frank Jenko
The pursuit of fusion energy is gaining momentum, driven by factors including advances in high-performance computing. As the need for sustainable energy solutions grows ever more urgent, supercomputing emerges as a key enabler, accelerating fusion power toward practical realization. Supercomputers empower researchers to simulate complex plasma dynamics with remarkable precision, aiding in the prediction and optimization of plasma confinement and stability – both essential for sustaining burning plasmas. They also have a critical role in assessing the resilience of materials exposed to the extreme conditions of future fusion power plants. As the fusion community transitions from laboratory experiments to pilot plants, supercomputing bridges the gap between scientific discovery and engineering implementation, and it promises to reduce costs and shorten development timelines.
Computational science, Plasma physics
Physical Review Letters
Emergence of Navier-Stokes Hydrodynamics in Chaotic Quantum Circuits
Research article | Nonequilibrium statistical mechanics | 2025-06-10 06:00 EDT
Hansveer Singh, Ewan McCulloch, Sarang Gopalakrishnan, and Romain Vasseur
We construct an ensemble of two-dimensional nonintegrable quantum circuits that are chaotic but have a conserved particle current, and thus a finite Drude weight. The long-wavelength hydrodynamics of such systems is given by the incompressible Navier-Stokes equations. By analyzing circuit-to-circuit fluctuations in the ensemble we argue that these are negligible, so the circuit-averaged value of transport coefficients like the viscosity is also (in the long-time limit) the value in a typical circuit. The circuit-averaged transport coefficients can be mapped onto a classical irreversible Markov process. Therefore, remarkably, our construction allows us to efficiently compute the viscosity of a family of strongly interacting chaotic two-dimensional quantum systems.
Phys. Rev. Lett. 134, 230401 (2025)
Nonequilibrium statistical mechanics, Quantum circuits, Quantum statistical mechanics, Stochastic processes, Transport phenomena
Entanglement Patterns of Quantum Chaotic Hamiltonians with a Scalar U(1) Charge
Research article | Eigenstate thermalization | 2025-06-10 06:00 EDT
Christopher M. Langlett and Joaquin F. Rodriguez-Nieva
Our current understanding of quantum chaos in many-body quantum systems hinges on the random matrix theory (RMT) behavior of eigenstates and their energy level statistics. Although RMT has been remarkably successful in describing ‘’coarse’’ features of many-body quantum Hamiltonians in chaotic regimes, such as the Wigner-Dyson level spacing statistics or the volume-law behavior of eigenstate entanglement entropy, it remains a challenge to describe their ‘’finer’’ features, particularly those arising from spatial locality. Here, we show that we can accurately describe the statistical behavior of eigenstate ensembles in many-body Hamiltonians by using pure random states with physical constraints that capture the essential features of the Hamiltonian, specifically spatial locality and symmetries. We demonstrate our approach on local spin Hamiltonians with a scalar U(1) charge. By constructing ensembles of constrained random states that account for two commuting scalar charges playing the role of energy and magnetization, we describe the patterns of entanglement of midspectrum eigenstates beyond their average volume-law behavior, including $O(1)$ corrections and fluctuations, analytically and numerically. When defining the correspondence between quantum chaotic eigenstates in many-body Hamiltonians and RMT ensembles, our work highlights the important role played by spatial locality in describing universal features beyond the volume-law behavior.
Phys. Rev. Lett. 134, 230402 (2025)
Eigenstate thermalization, Quantum information theory, Quantum statistical mechanics, Quantum thermodynamics, 1-dimensional spin chains, Quantum many-body systems, Quantum spin models, Information theory, Random matrix theory
Space-Time Correlations in Monitored Kinetically Constrained Discrete-Time Quantum Dynamics
Research article | Open quantum systems | 2025-06-10 06:00 EDT
Marcel Cech, María Cea, Mari Carmen Bañuls, Igor Lesanovsky, and Federico Carollo
State-of-the-art quantum simulators permit local temporal control of interactions and midcircuit readout. These capabilities open the way toward the exploration of intriguing nonequilibrium phenomena. We illustrate this with a kinetically constrained many-body quantum system that has a natural implementation on Rydberg quantum simulators. The evolution proceeds in discrete time and is generated by repeatedly entangling the system with an auxiliary environment that is monitored and reset after each time step. Despite featuring an uncorrelated infinite-temperature average stationary state, the dynamics displays coexistence of fast and slow space-time regions in stochastic realizations of the system state. The time record of measurement outcomes on the environment serves as natural probe for such dynamical heterogeneity, which we characterize using tools from large deviation theory. Our Letter establishes the large deviation framework for discrete-time open quantum many-body systems as a means to characterize complex dynamics and collective phenomena in quantum processors and simulators.
Phys. Rev. Lett. 134, 230403 (2025)
Open quantum systems, Quantum simulation, Stochastic dynamical systems, Kinetically constrained models, Large deviation & rare event statistics, Stochastic processes & statistics
Impediment to Torsion from Spectral Geometry
Alternative gravity theories | 2025-06-10 06:00 EDT
Arkadiusz Bochniak, Ludwik Dąbrowski, Andrzej Sitarz, and Paweł Zalecki
Modifications of standard general relativity that bring torsion into the game have a long-standing history. However, no convincing arguments exist for or against its presence in physically acceptable gravity models. In this Letter, we provide an argument based on spectral geometry (using methods of pseudodifferential calculus) that suggests that the torsion shall be excluded from the consideration. We demonstrate that there is no well-defined functional extending to the torsion-full case of the spectral formulation of the Einstein tensor.
Phys. Rev. Lett. 134, 231501 (2025)
Alternative gravity theories, General relativity formalism, Gravitation
Suppression of Spin Transfer to $\mathrm{\Lambda }$ Hyperon in Deep-Inelastic Scattering
Research article | Deep inelastic scattering | 2025-06-10 06:00 EDT
Xiaoyan Zhao, Zuo-tang Liang, Tianbo Liu, and Ya-jin Zhou
We investigate $\mathrm{\Lambda }$ production in semi-inclusive deep-inelastic scattering using a polarized lepton beam and find that the spin transfer is significantly suppressed by target fragmentation. As further demonstrated by a model estimation, experimental data can be well described once the target fragmentation is taken into account, which alleviates the tension with calculations solely based on current fragmentation. Our findings suggest that, at the energies of existing fixed-target experiments, the separation of current and target fragmentation regions is not distinct. Spin transfer as well as other spin effects offers a sensitive probe into the origin of the produced hadron.
Phys. Rev. Lett. 134, 231901 (2025)
Deep inelastic scattering, Fragmentation functions, Fragmentation into hadrons, Polarization in interactions & scattering, Hyperons, Spin
New Angles on Energy Correlators
Research article | Quantum chromodynamics | 2025-06-10 06:00 EDT
Samuel Alipour-fard, Ankita Budhraja, Jesse Thaler, and Wouter J. Waalewijn
Energy correlators have recently come to the forefront of jet substructure studies at colliders due to their remarkable properties: they naturally separate physics at different scales, are robust to contamination from soft radiation, and offer a direct connection with quantum field theory. The current parametrization used for energy correlators, however, is based on redundant pairwise angles with complex phase space restrictions. In this Letter, we introduce a new parametrization of energy correlators that features a simpler phase space structure and preserves information about the orientation of jet constituents. Further, our parametrization drastically reduces the computational cost to compute energy correlators on experimental data; whereas the time to compute a traditional projected $N$-point energy correlator scales as ${M}^{N}/N!$ on a jet with $M$ particles, our new parametrization achieves a scaling of ${M}^{2}\mathrm{ln}M$, remarkably independently of $N$. Even for $N=3$, this improved scaling is particularly important for studies of heavy ion collisions, and higher values of $N$ will enable new qualitative understanding of gauge theories. Theoretical calculations for our new energy correlators differ from those of traditional parametrizations only at next-to-next-to-leading logarithmic accuracy and beyond, and we expect that our simpler phase space structure will simplify those calculations. We also discuss how to extend our parametrization to resolved $N$-point energy correlators that encode angular distances between greater numbers of particles, yielding intuitive visualizations of jet substructure that are qualitatively different for different jet samples. We propose two possible generalizations for probing multiprong jets and testing jet scaling behavior.
Phys. Rev. Lett. 134, 231902 (2025)
Quantum chromodynamics, Quark & gluon jets
Precision Mass Measurements Reveal Low Neutron Pairing in Tin beyond $N=82$ and Its Impact on Stellar Nucleosynthesis
Research article | Binding energy & masses | 2025-06-10 06:00 EDT
A. Mollaebrahimi et al.
We present a study on neutron-rich tin ($Z=50$) isotopes beyond the doubly closed shell of $N=82$ through high-precision mass measurements, including the first-ever measurements of the masses of $^{136}\mathrm{Sn}$, $^{137}\mathrm{Sn}$, and $^{138}\mathrm{Sn}$ isotopes. These measurements enhance our understanding of the nuclear structure and astrophysical nucleosynthesis in this previously unexplored region. The new mass data are used for evaluation of the final abundances of mass numbers $A=135$ and 137 in $r$-process network calculations. Our findings reveal a notable change in the empirical pairing gap for tin isotopes beyond the $N=82$ closed shell and a shift in the two-neutron-separation energy slope compared to heavier elements above the shell closure. A new set of ab initio calculations effectively describes these observed trends.
Phys. Rev. Lett. 134, 232701 (2025)
Binding energy & masses, Nuclear astrophysics, Nuclear binding, Rare & new isotopes, Secondary beams
Nonlinear Calcium King Plot Constrains New Bosons and Nuclear Properties
Research article | Atomic, optical & lattice clocks | 2025-06-10 06:00 EDT
Alexander Wilzewski et al.
*et al.*A hypothetical fifth force could be detected by its effect on the optical transition frequencies of an element’s different isotopes.
Phys. Rev. Lett. 134, 233002 (2025)
Atomic, optical & lattice clocks, Coherent control, Single- and few-photon ionization & excitation, Trapped ions, 39 ≤ A ≤ 58, Coupled cluster
Magnetic Signatures of Pressure-Induced Multicomponent Superconductivity in ${\mathrm{UTe}}_{2}$
Research article | Penetration depth | 2025-06-10 06:00 EDT
Zheyu Wu, Jiasheng Chen, Theodore I. Weinberger, Andrej Cabala, Vladimír Sechovský, Michal Vališka, Patricia L. Alireza, Alexander G. Eaton, and F. Malte Grosche
The phase diagram of the heavy fermion compound ${\mathrm{UTe}}{2}$ contains multiple superconducting phases, several of which show characteristics of odd-parity pairing. We have investigated the pressure dependence of the superconducting transition in high-quality crystals of ${\mathrm{UTe}}{2}$ by tracking its signature in the magnetic susceptibility $\chi (T)$. A single, sharp superconducting transition is observed at low pressures $<0.3\text{ }\text{ }\mathrm{GPa}$. At higher pressure, a second feature emerges in $\chi (T)$, which is located at the lower-temperature superconducting phase boundary previously identified in specific heat measurements. This second transition anomaly in $\chi (T)$ can be attributed to a step change in the London penetration depth, providing direct evidence for a change in the superconducting order parameter of ${\mathrm{UTe}}{2}$. Thermodynamic constraints suggest that the low temperature, high pressure superconducting state is distinct from zero pressure superconductivity as well as from the high pressure, high temperature superconducting state, raising the possibility of multicomponent superconductivity in high pressure ${\mathrm{UTe}}{2}$.
Phys. Rev. Lett. 134, 236501 (2025)
Penetration depth, Superconducting order parameter, Superconducting phase transition, Superconductivity
Bulk-Boundary Correspondence of Fractonic Field Theories
Research article | Fractional quantum Hall effect | 2025-06-10 06:00 EDT
Bhandaru Phani Parasar, Yuval Gefen, and Vijay B. Shenoy
We develop a theory of edge excitations of fractonic systems in two dimensions, and elucidate their connections to bulk transport properties and quantum statistics of bulk excitations. The system we consider has immobile point charges, dipoles constrained to move only along lines perpendicular to their moment, and freely mobile quadrupoles and higher multipoles, realizing a bulk fractonic analog of fractional quantum Hall phases. We demonstrate that a quantized braiding phase between two bulk excitations is obtained only in two cases: when a point quadrupole braids around an immobile point charge, or when two non-orthogonal point dipoles braid with one another. The presence of a boundary edge in the system entails two types of gapless edge excitation modes, one that is fractonic with immobile charges and longitudinal dipoles, and a second non-fractonic mode consisting of transverse dipoles. We derive a novel current algebra of the fractonic edge modes. Further, investigating the effect of local edge-to-edge tunneling on these modes, we find that such a process is a relevant perturbation suggesting the possibility of edge deformation.
Phys. Rev. Lett. 134, 236601 (2025)
Fractional quantum Hall effect, Fractons, Topological order
Causal-Constraint Broadband Sound Absorption under Isothermal Process
Research article | Acoustic metamaterials | 2025-06-10 06:00 EDT
Chuanhao Ge, Nengyin Wang, Xu Wang, and Yong Li
Causality, a cornerstone of physical laws, fundamentally links a system’s structural characteristics to its wave interaction properties, such as the minimum thickness of acoustic absorbers required for specific absorption spectra. Traditional causality principles for sound absorption are derived under the assumption of adiabatic sound propagation. In this Letter, we propose a generalized causal framework that incorporates isothermal processes, accounting for nonslip boundary conditions at the fluid-solid interface. These conditions introduce velocity and temperature gradients, challenging the conventional adiabatic assumption. To validate our framework, we analyze two distinct absorber types: a metamaterial with multiresonant units and a metafoam with multilayer double-porosity structures. Our theoretical and experimental studies reveal that absorber thickness can exceed the adiabatic limit, being instead governed by isothermal constraints. This paradigm shift deepens the understanding of sound absorption mechanisms and paves the way for designing high-performance acoustic devices that approach fundamental performance limits.
Phys. Rev. Lett. 134, 237001 (2025)
Acoustic metamaterials, Liquid-solid interfaces, Acoustic techniques
Double Splay Nematic Order in Confined Polar Fluids
Research article | Flexoelectrics | 2025-06-10 06:00 EDT
Zhongjie Ma, Miao Jiang, Aile Sun, Shengzhu Yi, Jidan Yang, Mingjun Huang, Satoshi Aya, and Qi-Huo Wei
A double splay nematic phase is observed experimentally for the first time in the ferroelectric liquid crystal RM734 under cationic polymer coated planar confinement.
Phys. Rev. Lett. 134, 238101 (2025)
Flexoelectrics, Topological defects, Ferroelectric liquid crystals, Liquid crystals, Nematic liquid crystals
Physical Review X
Fault-Tolerant Logical Measurements via Homological Measurement
Research article | Quantum error correction | 2025-06-10 06:00 EDT
Benjamin Ide, Manoj G. Gowda, Priya J. Nadkarni, and Guillaume Dauphinais
A new framework, homological measurement, enables fault-tolerant logical operations across a broad class of quantum error-correction codes known as CSS codes.
Phys. Rev. X 15, 021088 (2025)
Quantum error correction, Quantum gates
Nonequilibrium Dynamics of Long-Range Interacting Fermions
Research article | Cavity quantum electrodynamics | 2025-06-10 06:00 EDT
T. Zwettler, G. Del Pace, F. Marijanovic, S. Chattopadhyay, T. Bühler, C.-M. Halati, L. Skolc, L. Tolle, V. Helson, G. Bolognini, A. Fabre, S. Uchino, T. Giamarchi, E. Demler, and J. P. Brantut
Ultracold fermions in a cavity self-organize into a charge-density wave up to 10 times faster than short-range interacting atoms, showing that long-range interactions can dramatically accelerate quantum phase transitions.
Phys. Rev. X 15, 021089 (2025)
Cavity quantum electrodynamics, Fermi gases, Fermionic condensates
arXiv
Physics-Informed Neural Operators for Generalizable and Label-Free Inference of Temperature-Dependent Thermoelectric Properties
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Hyeonbin Moon, Songho Lee, Wabi Demeke, Byungki Ryu, Seunghwa Ryu
Accurate characterization of temperature-dependent thermoelectric properties (TEPs), such as thermal conductivity and the Seebeck coefficient, is essential for reliable modeling and efficient design of thermoelectric devices. However, their nonlinear temperature dependence and coupled transport behavior make both forward simulation and inverse identification difficult, particularly under sparse measurement conditions. In this study, we develop a physics-informed machine learning approach that employs physics-informed neural networks (PINN) for solving forward and inverse problems in thermoelectric systems, and neural operators (PINO) to enable generalization across diverse material systems. The PINN enables field reconstruction and material property inference by embedding governing transport equations into the loss function, while the PINO generalizes this inference capability across diverse materials without retraining. Trained on simulated data for 20 p-type materials and evaluated on 60 unseen materials, the PINO model demonstrates accurate and label-free inference of TEPs using only sparse field data. The proposed framework offers a scalable, generalizable, and data-efficient approach for thermoelectric property identification, paving the way for high-throughput screening and inverse design of advanced thermoelectric materials.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
main - 31pages, 9 figures / supplementary - 11pages, 3 figures
Comparison between the diffusion properties of different small-scale fractional transport models
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Stochastic transport due to a velocity field modeled by the superposition of small-scale divergence free vector fields activated by Fractional Gaussian Noises (FGN) is numerically investigated. We present two non-trivial contributions: the first one is the definition of a model where different space-time structures can be compared on the same ground: this is achieved by imposing the same average kinetic energy to a standard Ornstein-Uhlenbeck approximation, then taking the limit to the idealized white noise structure. The second contribution, based on the previous one, is the discover that a mixing spatial structure with persistent FGN in the Fourier components induces a classical Brownian diffusion of passive particles, with suitable diffusion coefficient; namely, the memory of FGN is lost in the space complexity of the velocity field.
Statistical Mechanics (cond-mat.stat-mech)
Domain Switching on the Pareto Front: Multi-Objective Deep Kernel Learning in Automated Piezoresponse Force Microscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Yu Liu, Utkarsh Pratiush, Kamyar Barakati, Hiroshi Funakubo, Ching-Che Lin, Jaegyu Kim, Lane W. Martin, Sergei V. Kalinin
Ferroelectric polarization switching underpins the functional performance of a wide range of materials and devices, yet its dependence on complex local microstructural features renders systematic exploration by manual or grid-based spectroscopic measurements impractical. Here, we introduce a multi-objective kernel-learning workflow that infers the microstructural rules governing switching behavior directly from high-resolution imaging data. Applied to automated piezoresponse force microscopy (PFM) experiments, our framework efficiently identifies the key relationships between domain-wall configurations and local switching kinetics, revealing how specific wall geometries and defect distributions modulate polarization reversal. Post-experiment analysis projects abstract reward functions, such as switching ease and domain symmetry, onto physically interpretable descriptors including domain configuration and proximity to boundaries. This enables not only high-throughput active learning, but also mechanistic insight into the microstructural control of switching phenomena. While demonstrated for ferroelectric domain switching, our approach provides a powerful, generalizable tool for navigating complex, non-differentiable design spaces, from structure-property correlations in molecular discovery to combinatorial optimization across diverse imaging modalities.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Artificial Intelligence (cs.AI), Machine Learning (cs.LG)
Emblems of pair density waves: dual identity of topological defects and their transport signatures
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
Omri Lesser, Chunli Huang, James P. Sethna, Eun-Ah Kim
The pair density wave (PDW) exemplifies intertwined orders in strongly correlated systems. A recent discovery of superconductivity in a quarter-metal state offers the first experimental system where a pure PDW without uniform superconductivity is suspected, offering a unique opportunity to examine the consequences of intertwined orders. A pure two-dimensional PDW supports an unusual fractional excitation as its topological defect (TD). A TD simultaneously winds the phase of the Cooper pair and distorts the amplitude modulation – a dual role reflecting its intertwined character. As a vortex, a TD carries fractional vorticity of $ \frac{1}{3} h/2e$ , whose movement would cause resistance. As a crystalline defect, a TD can be sourced by charge disorder in the system. We show that experimentally observed resistive switching can originate from mobile TDs, while a small magnetic field will restore zero resistance by blocking their motion. The resulting resistive state exhibits extreme anisotropy and a Hall response, with the Hall angle determined by the angle between the current and the TD’s Burgers vector. These features will serve as confirmation of the dual identity of topological defects as emblems of PDW order.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
4+6 pages, 4 figures
Altermagnet-Superconductor Heterostructure: a Scalable Platform for Braiding of Majorana Modes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Themba Hodge, Eric Mascot, Stephan Rachel
Topological quantum computation, featuring qubits built out of anyonic excitations known as Majorana zero modes (MZMs), have long presented an exciting pathway towards scalable quantum computation. Recently, the advent of altermagnetic materials has presented a new pathway towards localized MZMs on the boundary of two-dimensional materials, consisting of an altermagnetic film, subject to a superconducting proximity effect from a superconducting substrate. In this work, we demonstrate the possibility for an altermagnet-superconductor heterostructure, to not only harbor MZMs, but also freely manipulate their position along the topological boundary of the material, via rotation of the Néel vector. Using this mechanism, on a square platform, we utilize a time-dependent method to simulate the Z-gate via braiding, and then extend this to a larger H-junction, where we implement the $ \sqrt{X}$ and $ \sqrt{Z}$ gate on a single-qubit system. Further, this structure is eminently scalable to many-qubit systems, thus providing the essential ingredients towards universal quantum computation.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
5 pages, 3 figures
Composite Superconducting Orders and Magnetism in CeRh$_2$As$_2$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
Fabian Jakubczyk, Julia M. Link, Carsten Timm
Locally noncentrosymmetric materials are attracting significant attention due to the unique phenomena associated with sublattice degrees of freedom. The recently discovered heavy-fermion superconductor CeRh$ _2$ As$ _2$ has emerged as a compelling example of this class, garnering widespread interest for its remarkable temperature-magnetic-field phase diagram, which features a field-induced first-order superconductor-to-superconductor phase transition with nontrivial dependence on the field direction and high critical fields, as well as antiferromagnetic and potentially higher multipole orders. To investigate the complex interplay of the ordered phases in CeRh$ _2$ As$ _2$ , we develop a theoretical framework based on symmetry analysis combined with Bogoliubov–de Gennes and Landau methods. This approach allows us to propose probable symmetries of the superconducting states and elucidate their close relationship with magnetism. Intriguingly, we find that the first-order transition can be interpreted as a transition between coexistence phases of the same symmetry but with distinct admixtures of individual superconducting order parameters. This line may end in a critical endpoint below the superconducting critical temperature. Our approach accurately reproduces current experimental phase diagrams for varying temperature as well as out-of-plane and in-plane magnetic field, both if the transition to a magnetic phase occurs below the superconducting critical temperature and if it occurs above. Furthermore, we calculate the magnetic susceptibility and the specific heat and compare these quantities to recent experimental results.
Superconductivity (cond-mat.supr-con)
Defect complexes in CrSBr revealed through electron microscopy and deep learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Mads Weile, Sergii Grytsiuk, Aubrey Penn, Daniel G. Chica, Xavier Roy, Kseniia Mosina, Zdenek Sofer, Jakob Schiøtz, Stig Helveg, Malte Rösner, Frances M. Ross, Julian Klein
Atomic defects underpin the properties of van der Waals materials, and their understanding is essential for advancing quantum and energy technologies. Scanning transmission electron microscopy is a powerful tool for defect identification in atomically thin materials, and extending it to multilayer and beam-sensitive materials would accelerate their exploration. Here we establish a comprehensive defect library in a bilayer of the magnetic quasi-1D semiconductor CrSBr by combining atomic-resolution imaging, deep learning, and ab-initio calculations. We apply a custom-developed machine learning work flow to detect, classify and average point vacancy defects. This classification enables us to uncover several distinct Cr interstitial defect complexes, combined Cr and Br vacancy defect complexes and lines of vacancy defects that extend over many unit cells. We show that their occurrence is in agreement with our computed structures and binding energy densities, reflecting the intriguing layer interlocked crystal structure of CrSBr. Our ab-initio calculations show that the interstitial defect complexes give rise to highly localized electronic states. These states are of particular interest due to the reduced electronic dimensionality and magnetic properties of CrSBr and are furthermore predicted to be optically active. Our results broaden the scope of defect studies in challenging materials and reveal new defect types in bilayer CrSBr that can be extrapolated to the bulk and to over 20 materials belonging to the same FeOCl structural family.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
main: 13 pages, 6 figures, 1 table; SM: 32 pages, 25 figures, 4 tables
Phys. Rev. X 15, 021080 (2025)
Sharp spectroscopic fingerprints of disorder in an incompressible magnetic state
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Chaebin Kim, Sumedh Rathi, Naipeng Zhang, Arnab Seth, Nikolai V. Simonov, Aya Rutherford, Long Chen, Haidong Zhou, Cheng Peng, Mingyu Xu, Weiwei Xie, Advik D. Vira, Mengkun Tian, Mykhaylo Ozerov, Itamar Kimchi, Martin Mourigal, Dmitry Smirnov, Zhigang Jiang
Disorder significantly impacts the electronic properties of conducting quantum materials by inducing electron localization and thus altering the local density of states and electric transport. In insulating quantum magnetic materials the effects of disorder are less understood and can drastically impact fluctuating spin states like quantum spin liquids. In the absence of transport tools, disorder is typically characterized using chemical methods or by semi-classical modeling of spin dynamics. This requires high magnetic fields that may not always be accessible. Here, we show that magnetization plateaus – incompressible states found in many quantum magnets – provide an exquisite platform to uncover otherwise undetectable amounts of disorder, regardless of the origin of the plateau. Using optical magneto-spectroscopy on the Ising-Heisenberg triangular-lattice antiferromagnet K$ _2$ Co(SeO$ _3$ )$ _2$ exhibiting a 1/3 magnetization plateau, we identify sharp spectroscopic lines, the fine structure of which serves as a hallmark signature of disorder. Through analytical and numerical modeling, we show that these fingerprints not only enable us to quantify minute amounts of disorder but also reveal its nature – as dilute vacancies. Remarkably, this model explains all details of the thermomagnetic response of our system, including the existence of multiple plateaus. Our findings provide a new approach to identifying disorder in quantum magnets.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn), Strongly Correlated Electrons (cond-mat.str-el)
19 pages, 14 figures, includes Supplementary Information
Wave-function microscopy: Derivation and anatomy of exact algebraic spinful wave functions and full Wigner-molecular spectra of a few highly correlated rapidly rotating ultracold fermionic atoms
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-11 20:00 EDT
Constantine Yannouleas, Uzi Landman
Exploring strongly correlated spinful states of few fermionic ultracold atoms in a rapidly rotating trap, an example of which was recently realized for two fermionic $ ^6$ Li atoms in an optical tweezer, we derive analytical (algebraic) total-spin-eigenstate wavefunctions through the development and employment of a theoretical platform that integrates exact numerical diagonalization (full configuration interaction, FCI) with symbolic language processing. For such rapid rotations, where the atoms occupy the lowest Landau level (LLL), the obtained algebraic expressions can address the full LLL spectrum in all its complexity, demonstrating that their spatial, spectral, and spin characteristics manifest formation of collectively rotating and vibrating Wigner molecules. The explicitly exhibited analytic wavefunctions (for two and three spinful $ ^6$ Li atoms) reproduce precisely the corresponding numerical FCI results, and they are shown to reach beyond the limited range of applicability of previous Jastrow-type treatments. These results, and their extension to bosonic systems, provide the impetus and analysis tools for future experimental and theoretical simulations of larger mesoscopic systems
Quantum Gases (cond-mat.quant-gas), Nuclear Theory (nucl-th), Quantum Physics (quant-ph)
16 pages with 5 color figures. Accepted for publication in Phys. Rev. A. For related papers, see this https URL
On a structure preserving closure of Langevin dynamics
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Travis Leadbetter, Prashant K. Purohit, Celia Reina
Given a particle system obeying overdamped Langevin dynamics, we demonstrate that it is always possible to construct a thermodynamically consistent macroscopic model which obeys a gradient flow with respect to its non-equilibrium free energy. To do so, we significantly extend the recent Stochastic Thermodynamics with Internal Variables (STIV) framework, a method for producing macroscopic thermodynamic models far-from-equilibrium from the underlying mesoscopic dynamics and an approximate probability density of states parameterized with so-called internal variables. Though originally explored for Gaussian probability distributions, we here allow for an arbitrary choice of the approximate probability density while retaining a gradient flow dynamics. This greatly extends its range of applicability and automatically ensures consistency with the second law of thermodynamics, without the need for secondary verification. We demonstrate numerical convergence, in the limit of increasing internal variables, to the true probability density of states for both a multi-modal relaxation problem, a protein diffusing on a strand of DNA, and for an externally driven particle in a periodic landscape. Finally, we provide a reformulation of STIV with the quasi-equilibrium approximations in terms of the averages of observables of the mesostate, and show that these, too, obey a gradient flow.
Statistical Mechanics (cond-mat.stat-mech)
Pilot-waves and copilot-particles: A novel approach to objective collapse
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
We propose an extension of Schrödinger’s equation that incorporates the macroscopic measurement-induced wavefunction collapse phenomenon. Our approach relies on a hybrid between Bohm-de Broglie pilot-wave and objective collapse theories. The Bohmian particle is guided by the wavefunction and, conversely, the wavefunction gradually localizes towards the particle’s position. As long as the particle can visit any state, as in a typical microscopic system, the localization effect does not favor any particular quantum state and, on average, the usual Schrödinger-like time evolution results. However, when the wavefunction develops spatially well-separated lobes, as would happen during a macroscopic measurement, the Bohmian particle can remain trapped in one lobe, and the wavefunction eventually localizes there. The end result, in macroscopic systems, is a wavefunction collapse that is consistent with Born’s rule. We illustrate the theory with a simple double-slit experiment simulation.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
6 pages, 3 figures
Anomaly, Class Division, and Decoupling in Wealth Dynamics
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Jaeseok Hur, Meesoon Ha, Hawoong Jeong
Economic inequality is shaped by the agent-network structure, the interaction between agents, and the individual agent’s ability. We provide a comprehensive picture of anomalous diffusion, economic class division, and bimodal wealth distribution in an agent-based model, where the allocation of heterogeneous agent abilities/growth rates is tuned in sparse regular this http URL particular, we focus on the statistical characteristics of logarithmic scaled normalized wealth distributions with two ability parameters, assortativity $ \mathcal{A}$ and concentration $ \mathcal{R}$ . For the set of $ (\mathcal{A},\mathcal{R})$ , temporal behaviors of log-wealth distributions reveal that the decoupling between different ability groups depends primarily on $ \mathcal{R}$ and long-term inequality depends mainly on $ \mathcal{A}$ . In other words, class division and decoupling are driven by $ \mathcal{R}$ , while the super-diffusive nature in the leading class is driven by $ \mathcal{A}$ . Our findings highlight that hierarchical segregation of abilities, rather than ability differences alone, is a key driver of economic class stratification. Finally, our model provides a minimal, yet powerful framework for understanding the bimodal global income distribution observed over the past half century and highlights the critical role of network-level segregation in shaping economic inequality.
Statistical Mechanics (cond-mat.stat-mech), Physics and Society (physics.soc-ph)
18 pages,3 figures (main) and 11 figures (SM)
Visualizing a Terahertz Superfluid Plasmon in a Two-Dimensional Superconductor
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
Alexander von Hoegen, Tommy Tai, Clifford J. Allington, Matthew Yeung, Jacob Pettine, Marios H. Michael, Emil Viñas Boström, Xiaomeng Cui, Kierstin Torres, Alexander E. Kossak, Byunghun Lee, Geoffrey S. D. Beach, Angel Rubio, Philip Kim, Nuh Gedik
The superconducting gap defines the fundamental energy scale for the emergence of dissipationless transport and collective phenomena in a superconductor. In layered high-temperature cuprate superconductors, where the Cooper pairs are confined to weakly coupled two-dimensional copper-oxygen planes, terahertz (THz) spectroscopy at sub-gap millielectronvolt energies has provided crucial insights into the collective superfluid response perpendicular to the superconducting layers. However, within the copper-oxygen planes the collective superfluid response manifests as plasmonic charge oscillations at energies far exceeding the superconducting gap, obscured by strong dissipation. Here, we present spectroscopic evidence of a below-gap, two-dimensional superfluid plasmon in few-layer Bi2Sr2CaCu2O8+x and spatially resolve its deeply sub-diffractive THz electrodynamics. By placing the superconductor in the near-field of a spintronic THz emitter, we reveal this distinct resonance-absent in bulk samples and observed only in the superconducting phase-and determine its plasmonic nature by mapping the geometric anisotropy and dispersion. Crucially, these measurements offer a direct view of the momentum- and frequency dependent superconducting transition in two dimensions. These results establish a new platform for investigating superfluid phenomena at finite momenta and THz frequencies, highlighting the potential to engineer and visualize superconducting devices operating at ultrafast THz rates.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
23 pages, 4 figures
Dimerization of Ag adatoms on Si(100) at surprisingly low temperature due to adatom migration on top of Si-dimer rows
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Alejandro Peña-Torres, Michail Stamatakis, Hannes Jónsson
The puzzling experimental observations of Ag addimer formation on the Si(100) surface upon vapor deposition at low temperature, even as low as 140 K, reported by Huang et al. [Phys. Chem. Chem. Phys. 2021, 23, 4161], is explained by facile thermal migration on top of the Si dimer rows, while diffusion is inactive once an Ag adatom lands in one of the optimal binding sites in between dimer rows. The previously hypothesized transient mobility due to the hot spot formed as an Ag atom lands on the Si surface is found not to contribute significantly to mobility and dimer formation. The experimental conditions are simulated by a combination of classical dynamics calculations of the deposition events, systematic searches of saddle points representing transition states for thermally activated events and kinetic Monte Carlo simulations of long timescale evolution of the system over a temperature range from 100 K to 300 K. While the calculated energy barriers for diffusion parallel and perpendicular to the Si dimer rows are found to be nearly equal, indicating isotropic diffusion, the simulations show highly anisotropic diffusion, as the optimal migration mechanism involves multiple hops of Ag adatoms on top of Si dimer rows. Impinging Ag atoms are found to have a 90% chance of landing on top of a dimer row and while the hot spot created cools down too fast for transient mobility to play an important role, the energy barrier for thermally activated hops along the dimer row is low enough for migration to be active even at 100 K. A migrating Ag adatom can dimerise with another Ag adatom sitting at a stable binding site in between rows or another adatom on top of the same row. The simulations for deposition at 140 K show that most of the deposited Ag atoms end up forming dimers.
Materials Science (cond-mat.mtrl-sci)
10 pages, 5 figures
Influence of atomic-scale defects on coherent phonon excitations by THz near fields in an STM
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Vibhuti N. Rai, Junyoung Sim, Florian Faaber, Nils Bogdanoff, Sergey Trishin, Paul Wiechers, Tom S. Seifert, Tobias Kampfrath, Christian Lotze, Katharina J. Franke
Coherent phonons describe the collective, ultrafast motion of atoms and play a central role in light-induced structural dynamics. Here, we employ terahertz scanning tunneling microscopy (THz-STM) to excite and detect coherent phonons in semiconducting 2H-MoTe$ _{2}$ and resolve how their excitation is influenced by atomic-scale defects. In a THz pump-probe scheme, we observe long-lived oscillatory signals that we assign to out-of-plane breathing and in-plane shear modes, which are both forbidden in the bulk. Remarkably, the relative excitation strength of these modes varies near defects, indicating that local band bending modulates the coupling to the THz field. This defect-tunable coupling offers new opportunities to control material properties via selective excitation of vibrational modes at the nanoscale.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 10 figures
AI-Assisted Rapid Crystal Structure Generation Towards a Target Local Environment
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Osman Goni Ridwan, Sylvain Pitié, Monish Soundar Raj, Dong Dai, Gilles Frapper, Hongfei Xue, Qiang Zhu
In the field of material design, traditional crystal structure prediction approaches require extensive structural sampling through computationally expensive energy minimization methods using either force fields or quantum mechanical simulations. While emerging artificial intelligence (AI) generative models have shown great promise in generating realistic crystal structures more rapidly, most existing models fail to account for the unique symmetries and periodicity of crystalline materials, and they are limited to handling structures with only a few tens of atoms per unit cell. Here, we present a symmetry-informed AI generative approach called Local Environment Geometry-Oriented Crystal Generator (LEGO-xtal) that overcomes these limitations. Our method generates initial structures using AI models trained on an augmented small dataset, and then optimizes them using machine learning structure descriptors rather than traditional energy-based optimization. We demonstrate the effectiveness of LEGO-xtal by expanding from 25 known low-energy sp2 carbon allotropes to over 1,700, all within 0.5 eV/atom of the ground-state energy of graphite. This framework offers a generalizable strategy for the targeted design of materials with modular building blocks, such as metal-organic frameworks and next-generation battery materials.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
14 pages, 7 figures
Spin-split superconductivity in spin-orbit coupled hybrid nanowires with ferromagnetic barriers
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
J. Zhao, A. Mazanik, D. Razmadze, Y. Liu, P. Krogstrup, F. S. Bergeret, S. Vaitiekėnas
We report transport studies of hybrid Josephson junctions based on semiconducting InAs nanowires with fully overlapping epitaxial ferromagnetic insulator EuS and superconducting Al partial shells. Current-biased measurements reveal a hysteretic superconducting window with a sizable supercurrent near the coercive field of the ferromagnetic insulator, accompanied by multiple Andreev reflections. Tunneling spectroscopy shows a superconducting gap characterized by three peaks, which we attribute to tunneling between exchange-split superconductors. A theoretical model reproduces the observed features and indicates that spin mixing, driven by sizable spin-orbit coupling, is essential to their formation. Our results demonstrate proximity-induced superconductivity through a ferromagnetic insulator and establish a new platform for exploring spin-triplet pairing.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
10 pages, 5+5 figures
Bound States at Semiconductor – Mott Insulator Interfaces
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-11 20:00 EDT
Utilizing the hierarchy of correlations in the context of a Fermi-Hubbard model, we deduce the presence of quasi-particle bound states at the interface between a Mott insulator and a semiconductor, as well as within a semiconductor-Mott-semiconductor heterostructure forming a quantum well. In the case of the solitary interface, the existence of bound states necessitates the presence of an additional perturbation with a minimal strength depending on the spin background of the Mott insulator. Conversely, within the quantum well, this additional perturbation is still required to have bound states while standing-wave solutions even exist in its absence.
Strongly Correlated Electrons (cond-mat.str-el)
A non-local exchange potential for electronic structure calculations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
In this work we describe a model for the exchange interaction of electrons, as it follows from the Pauli exclusion principle. Starting from Hartree-Fock theory and making use of the free electron-gas model we propose a simple scheme to calculate the exchange-potential for atoms as well as simple molecules and solids. This method assures the correct asymptotic long-range behavior of the potential, contrary to local-density approximations that rely on a strongly simplified generalization of the well-known Kohn-Sham or Slater exchange interaction. Furthermore, our results approach the Kohn-Sham results in the interstitial space of solids. As a benchmark test, total energies and eigenenergies for atoms from He to Xe computed within our model are compared to other calculations as well as to experimental data.
Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
24 pages, 7 figures
Spontaneously broken chiral symmetry in the interacting Kane-Mele model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-11 20:00 EDT
Minghuan Zeng, Junjie Zeng, Ling Qin, Shiping Feng, Donghui Xu, Rui Wang
The essential properties of the half-filled interacting Kane-Mele model on a hexagon lattice is
studied using the slave rotor approach. It is shown clearly that a long-range charge-order state with
spontaneously broken chiral symmetry emerges in the weak and moderate interaction regimes, as
well as a presumed site-selected topological Mott insulator state in the stronger interaction regime
with U < UMott, where UMott is the critical interaction strength, and in the case of U > UMott,
the system is transited into the usual topological Mott state. This new charge-order state has
lower energy compared to the usual topological band insulator (TBI) state with chiral symmetry,
and thus is named as non-chiral TBI state. More specifically, in this non-chiral TBI state without
any long-range magnetic order, a long-range charge order with different electron occupation on
two sublattices appears in the absence of external sublattice field. The spontaneously broken chiral
symmetry gives rise to a special helical edge state, which has different spin accumulation on opposite
edges of the cylinder with periodic boundary condition in the zigzag direction, and thus leads to
a net spin current across the system. This net spin current would be further strengthened if the
nearest neighbor electron Coulomb interaction is taken into account as well, because it is favorable
for the long-range charge order with different electron occupation on sublattices.
Strongly Correlated Electrons (cond-mat.str-el)
18 pages, 11 figures
Diffusive spreading of a polydisperse polymer solution in a channel
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Long DNA molecules can be mapped by cutting them with restriction enzymes inside a narrow channel. Once cut, the individual fragments thus produced move away from each other due to diffusion and entropic effects. We investigate how long it takes for these fragments to travel distances large enough for an experimental device to distinguish them and (possibly) estimate their size. In essence, this is a single-file diffusion process in which molecules of different sizes and hence different diffusion coefficients spread out from an initially dense configuration. We use Monte Carlo methods to investigate this class of problems and define the time taken to reach the required final state as a first-passage \textit{spreading time}. Our results demonstrate that the stochastic nature of the diffusion process is as significant as the specifics of the molecular size distribution in determining the spreading time. We examine the relationship between the spreading time and the final space occupied by the fragments as a function of the experimental parameters and determine the fundamental length scale governing this process. We introduce a molecular sequence randomness parameter, $ Z$ , which is linearly correlated with the final spreading time. Finally, we show that the distribution function of spreading times follows a well-known form for first-passage time problems, and that its variance decreases linearly with the number of fragments.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
9 figures, 9pages
Neuralized Fermionic Tensor Networks for Quantum Many-Body Systems
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-06-11 20:00 EDT
Si-Jing Du, Garnet Kin-Lic Chan
We describe a class of neuralized fermionic tensor network states (NN-fTNS) that introduce non-linearity into fermionic tensor networks through configuration-dependent neural network transformations of the local tensors. The construction uses the fTNS algebra to implement a natural fermionic sign structure and is compatible with standard tensor network algorithms, but gains enhanced expressivity through the neural network parametrization. Using the 1D and 2D Fermi-Hubbard models as benchmarks, we demonstrate that NN-fTNS achieve order of magnitude improvements in the ground-state energy compared to pure fTNS with the same bond dimension, and can be systematically improved through both the tensor network bond dimension and the neural network parametrization. Compared to existing fermionic neural quantum states (NQS) based on Slater determinants and Pfaffians, NN-fTNS offer a physically motivated alternative fermionic structure. Furthermore, compared to such states, NN-fTNS naturally exhibit improved computational scaling and we demonstrate a construction that achieves linear scaling with the lattice size.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Strongly Correlated Electrons (cond-mat.str-el)
Developing a Neural Network Machine Learning Interatomic Potential for Molecular Dynamics Simulations of La-Si-P Systems
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Ling Tang, Weiyi Xia, Gayatri Viswanathan, Ernesto Soto, Kirill Kovnir, Cai-Zhuang Wang
While molecular dynamics (MD) is a very useful computational method for atomistic simulations, modeling the interatomic interactions for reliable MD simulations of real materials has been a long-standing challenge. In 2007, Behler and Perrinello first proposed and demonstrated an artificial neural network machine learning (ANN-ML) scheme, opening a new paradigm for developing accurate and efficient interatomic potentials for reliable MD simulation studies of the thermodynamics and kinetics of materials. In this paper, we show that an accurate and transferable ANN-ML interatomic potential can be developed for MD simulations of La-Si-P system. The crucial role of training data in the ML potential development is discussed. The developed ANN-ML potential accurately describes not only the energy versus volume curves for all the known elemental, binary, and ternary crystalline structures in La-Si-P system, but also the structures of La-Si-P liquids with various compositions. Using the developed ANN-ML potential, the melting temperatures of several crystalline phases in La-Si-P system are predicted by the coexistence of solid-liquid phases from MD simulations. While the ANN-ML model systematically underestimates the melting temperatures of these phases, the overall trend agrees with experiment. The developed ANN-ML potential is also applied to study the nucleation and growth of LaP as a function of different relative concentrations of Si and P in the La-Si-P liquid, and the obtained results are consistent with experimental observations.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn), Chemical Physics (physics.chem-ph)
Micro-Macro Modeling of Polymeric Fluids with Multi-Bead Polymer Chain
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Xuelian Bao, Lidong Fang, Huaxiong Huang, Zilong Song, Shixin Xu
This work extends the classical dumbbell (two-bead) model of polymer chains to a more detailed multi-bead representation, where each polymer chain consists of $ N$ beads connected by $ N-1$ springs. We develop a thermodynamically consistent micro-macro model based on the energy variational method to describe the coupled dynamics of polymer configurations and fluid flow. The resulting framework captures complex microscopic behaviors, such as bond stretching and alignment under flow, and links them to macroscopic stress responses.
Soft Condensed Matter (cond-mat.soft), Mathematical Physics (math-ph)
Exploring the energy landscape of the Thomson problem: local minima and stationary states
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Paolo Amore, Victor Figueroa, Enrique Diaz, Jorge A. López, Trevor Vincent
We conducted a comprehensive numerical investigation of the energy landscape of the Thomson problem for systems up to $ N=150$ . Our results show the number of distinct configurations grows exponentially with $ N$ , but significantly faster than previously reported. Furthermore, we find that the average energy gap between independent configurations at a given $ N$ decays exponentially with $ N$ , dramatically increasing the computational complexity for larger systems. Finally, we developed a novel approach that reformulates the search for stationary points in the Thomson problem (or similar systems) as an equivalent minimization problem using a specifically designed potential. Leveraging this method, we performed a detailed exploration of the solution landscape for $ N\leq24$ and estimated the growth of the number of stationary states to be exponential in $ N$ .
Soft Condensed Matter (cond-mat.soft), Computational Physics (physics.comp-ph)
28 pages, 13 figures
Exciton condensation from level repulsion: application to bilayer graphene
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-11 20:00 EDT
Harley D. Scammell, Oleg P. Sushkov
Exciton condensation in semiconductors and semimetals has long been predicted but remains elusive. In a semiconductor, condensation occurs when the exciton binding energy matches the band gap. This binding energy results from a balance between Coulomb attraction, which enhances it, and kinetic energy, which suppresses it. However, reducing kinetic energy typically increases screening, weakening Coulomb attraction. Empirically, in most candidate materials, the binding energy remains below the band gap, with few external parameters capable of altering this balance. Here, we propose an in-plane electric field as a control parameter. This field induces hybridisation between even- and odd-parity excitons, and the resulting level repulsion effectively enhances binding energy. We argue that this mechanism is generic to excitons in semiconductors and illustrate it with a model of biased bilayer graphene. Bilayer graphene is chosen since it has a tunable band gap, making it an excitonic condensate candidate and moreover, the Zener tunnelling rate contains, in addition to the usual exponential decay, a non-standard oscillating component – thanks to details of the electron dispersion. Analogous to quantum oscillations, we propose that Fourier spectrum of the current-voltage data allows for a novel test of exciton condensation. Finally, we show that the is a large excitonic gap to critical temperature ratio – a clear prediction for STM studies.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
Rogue waves collision under incident momentum modulation in two-component Bose-Einstein condensates
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-11 20:00 EDT
Zhihao Zhang, Tiantian Li, Xiao-Dong Bai, Yunbo Zhang, Denglong Wang
The collision dynamics of two first-order rogue waves (RWs) with opposite incident momentum in two-component Bose-Einstein condensates (BECs) is studied by solving the two-component one-dimensional Gross-Pitaevskii (GP) equation. It is demonstrated that the introduction of appropriate incident momentum successfully promotes the generation of second-order RWs in the case of relatively weaker interspecies interactions compared to intraspecific interactions. The range of incident momentum that can facilitate the generation of second-order RWs under different interspecies interaction strengths is determined, and machine learning is employed to find and analyze relationships among the interspecies interaction, the incident momentum, and the offset that can lead to the generation of second-order RWs. It shows that any two parameters above exhibit a positive or negative correlation when the third parameter is fixed. These findings provide additional possibilities for generating and controlling high-order RWs.
Quantum Gases (cond-mat.quant-gas), Chaotic Dynamics (nlin.CD), Quantum Physics (quant-ph)
Mic-hackathon 2024: Hackathon on Machine Learning for Electron and Scanning Probe Microscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Utkarsh Pratiush, Austin Houston, Kamyar Barakati, Aditya Raghavan, Dasol Yoon, Harikrishnan KP, Zhaslan Baraissov, Desheng Ma, Samuel S. Welborn, Mikolaj Jakowski, Shawn-Patrick Barhorst, Alexander J. Pattison, Panayotis Manganaris, Sita Sirisha Madugula, Sai Venkata Gayathri Ayyagari, Vishal Kennedy, Ralph Bulanadi, Michelle Wang, Kieran J. Pang, Ian Addison-Smith, Willy Menacho, Horacio V. Guzman, Alexander Kiefer, Nicholas Furth, Nikola L. Kolev, Mikhail Petrov, Viktoriia Liu, Sergey Ilyev, Srikar Rairao, Tommaso Rodani, Ivan Pinto-Huguet, Xuli Chen, Josep Cruañes, Marta Torrens, Jovan Pomar, Fanzhi Su, Pawan Vedanti, Zhiheng Lyu, Xingzhi Wang, Lehan Yao, Amir Taqieddin, Forrest Laskowski, Xiangyu Yin, Yu-Tsun Shao, Benjamin Fein-Ashley, Yi Jiang, Vineet Kumar, Himanshu Mishra, Yogesh Paul, Adib Bazgir, Rama chandra Praneeth Madugula, Yuwen Zhang, Pravan Omprakash, Jian Huang, Eric Montufar-Morales, Vivek Chawla, Harshit Sethi, Jie Huang, Lauri Kurki, Grace Guinan, Addison Salvador, Arman Ter-Petrosyan, Madeline Van Winkle, Steven R. Spurgeon, Ganesh Narasimha, Zijie Wu, Richard Liu, Yongtao Liu, Boris Slautin, Andrew R Lupini, Rama Vasudevan, Gerd Duscher, Sergei V. Kalinin
Microscopy is a primary source of information on materials structure and functionality at nanometer and atomic scales. The data generated is often well-structured, enriched with metadata and sample histories, though not always consistent in detail or format. The adoption of Data Management Plans (DMPs) by major funding agencies promotes preservation and access. However, deriving insights remains difficult due to the lack of standardized code ecosystems, benchmarks, and integration strategies. As a result, data usage is inefficient and analysis time is extensive. In addition to post-acquisition analysis, new APIs from major microscope manufacturers enable real-time, ML-based analytics for automated decision-making and ML-agent-controlled microscope operation. Yet, a gap remains between the ML and microscopy communities, limiting the impact of these methods on physics, materials discovery, and optimization. Hackathons help bridge this divide by fostering collaboration between ML researchers and microscopy experts. They encourage the development of novel solutions that apply ML to microscopy, while preparing a future workforce for instrumentation, materials science, and applied ML. This hackathon produced benchmark datasets and digital twins of microscopes to support community growth and standardized workflows. All related code is available at GitHub: this https URL
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG), Instrumentation and Detectors (physics.ins-det)
Revealing the Dominance of the Orbital Hall Effect over Spin in Transition Metal Heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
J. L. Costa, E. Santos, J. B. S. Mendes, A. Azevedo
We study inverse spin and orbital Hall effects in 19 transition metals using spin-pumping driven by ferromagnetic resonance. Spin-to-charge conversion was measured in YIG/X(5), while orbital-to-charge conversion was probed in YIG/Pt(2)/X(5) heterostructures. Here, X represents the different transition metals. Surprisingly, the orbital contribution overwhelmingly dominates over the spin response, clarifying the challenge of disentangling these effects. Our results largely agree with first-principles predictions for spin and orbital Hall conductivities but reveal discrepancies in select materials. These findings emphasize the fundamental role of the orbital Hall effect, and position orbitronics as a pivotal frontier in condensed matter physics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
7 pages, 4 figures
Theory of Semi-Deterministic Quantum Dot Placement in Heteroepitaxy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Achieving deterministic placement of self-assembled quantum dots (QDs) during epitaxial growth is essential for the reliable and efficient fabrication of high-quality single-photon sources and solid-state cavity quantum electrodynamics (cQED) systems, yet it remains a significant challenge due to the inherent stochasticity of QD nucleation processes. In this work, we theoretically demonstrate that deterministic QD nucleation within a pristine growth region can be achieved by engineering the boundary geometry of that region. During epitaxial growth, adatoms initially move toward the boundary and promote the formation of primary QDs along the boundary, driven by curvature and diffusion anisotropy. The resulting primary QDs distribution will generate many-body interactions that dynamically reshape the chemical potential landscape for subsequently deposited adatoms, enabling the formation of secondary QDs within the pristine growth region. These findings provide a theoretical foundation for reliable patterning of high optical-quality QDs, with potential applications in next-generation quantum photonic devices.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Computational Physics (physics.comp-ph)
Quasi-periodic flat-band model constructed by molecular-orbital representation
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Tomonari Mizoguchi, Yasuhiro Hatsugai
We construct a tight-binding model that hosts both a quasi-periodic nature and marcoscopically-dengenerate zero-energy modes. The model can be regarded as a counterpart of the Aubry-André-Harper (AAH) model, which is a paradigmatic example of the quasi-periodic tight-binding model. Our main focus is on the many-body state where the flat-band-like degenerate zero-energy modes are fully occupied. We find a characteristic sublattice dependence of the particle density distribution. Further, by analyzing the hyperuniformity of the particle density distribution, we find that it belongs to the class-I hyperuniform distribution, regardless of the model parameter. We also show that, upon changing the parameter, the finite-energy modes exhibit the same extended-to-localized transition as that for the original AAH model.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 11 figures
Vortices in Two-Dimensional Chiral Superfluids
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
We study the orbital angular momentum (OAM) $ L_z$ of two-dimensional chiral $ (p_x+ip_y)^{\nu}$ -wave superfluids (SFs) in the presence of an axisymmetric multiply quantized vortex (MQV) with vorticity $ k$ on a disk at zero temperature, in the framework of Bogoliubov-de Gennes (BdG) theory. Focusing on spectral asymmetry (or spectral flow), we find that $ L_z=(k+\nu)N/2$ for any integer $ \nu$ and $ k$ in the Bose-Einstein Condensation (BEC) regime, where $ N$ is the total number of fermions. While in the weak-pairing Bardeen-Cooper-Schrieffer (BCS) regime, only for chiral $ p+ip$ -wave SF with $ k=\pm 1$ , $ L_z=(k+\nu)N/2$ still holds. For chiral SFs with $ \nu\ge2$ or $ |k|\ge2$ in the BCS regime, the OAM $ L_z$ is remarkably reduced from its ``full” value in the BEC regime. However, the deviations differ in these two cases. For chiral SFs with $ \nu\ge2$ , $ L_z$ is sharply suppressed in this ideal setting with a specular wall, while the suppression caused by the $ |k| \ge 2$ vortex is moderate, which is core-size dependent. Furthermore, for $ p+ip$ -wave SF with $ k=-1$ , the total OAM $ L_z$ is zero, but the distribution $ L_z(r)$ is nontrivial compared with that of vortex-free $ s$ -wave SF, in which the total OAM is zero as well. For chiral SFs with $ \nu\ge2$ and $ |k|\ge2$ , the effects of circulation due to vortex and chiral pairing can coexist, and hence depress the OAM simultaneously. These observations can be explained by spectral asymmetry and unpaired fermions in the ground state of the BdG Hamiltonian. We also investigate the spatial distribution of particle density, OAM, by solving the BdG equation.
Superconductivity (cond-mat.supr-con)
9 pages, 4 figures
Bridging Electrostatic Screening and Ion Transport in Lithium Salt-Doped Ionic Liquids
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Hyungshick Park, Bong June Sung, Jeongmin Kim
Alkali salt-doped ionic liquids are emerging as promising electrolyte systems for energy applications, owing to their excellent interfacial stability. To address their limited ionic conductivity, various strategies have been proposed, including modifying the ion solvation environment and enhancing the transport of selected ions (e.g., Li$ ^+$ ). Despite the pivotal role of electrostatic interactions in determining key physicochemical properties, their influence on ion transport in such systems has received relatively little attention. In this work, we investigate the connection between ion transport and electrostatic screening using atomistic molecular dynamics simulations of 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([pyr$ _{14}$ ][TFSI]) doped with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) at molar fractions x$ _{LiTFSI}$ $ \le$ 0.3. We find that the charge-charge and density-density correlation functions exhibit oscillatory exponential decay, indicating that LiTFSI doped [pyr$ _{14}$ ][TFSI] is a charge- and mass-dense system. The electrostatic screening length decreases with increasing LiTFSI concentration, whereas the decay length of the density-density correlation functions remains nearly unchanged. Notably, we find that the x$ _{LiTFSI}$ -sensitive screening length serves as a central length scale for disentangling species-specific contributions of ion pairs to collective ion transport upon LiTFSI doping. This framework provides a unifying perspective on the interplay between structure and transport in ionic liquid systems.
Soft Condensed Matter (cond-mat.soft), Chemical Physics (physics.chem-ph)
11 pages, 5 figures
Non-Equilibrium Origin of Native Ring Anisotropy in Amorphous Systems
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-06-11 20:00 EDT
Native ring structures within amorphous networks play a critical role in determining structural and optical properties, in part due to their ability to host dopants such as rare earth ions in silicate systems. In this work, we demonstrate that the universal features of structural anisotropy in amorphous networks can be efficiently simulated using a model based on stochastically deformed, edge sharing N member native ring structures. This model isolates and characterizes the structural anisotropy generated during the annealing quenching process that is independent of any constituent specific interactions. We refer to this computational framework as Indistinguishable Simulated Folding (ISF), a stochastic process that mimics a simulated annealing quenching procedure. Formulated as a Markov process, ISF is governed by two physically meaningful parameters: the number of Markov steps, representing the mean duration of each ring folding event, and the stochastic deformation magnitude, which quantifies thermally induced structural changes per event. Furthermore, we show that the logarithm of any positive valued anisotropy measure generated by ISF is a skewed random variable, reflecting the growing entropy production rate during the Markov evolution. ISF provides both a conceptual framework for understanding the universal stochastic origin of structural anisotropy in amorphous networks and a practical tool for simulating constituent independent features, without requiring full scale molecular dynamics simulations.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
Observation of Uniform Supercurrent Flow in Polycrystalline K-doped Ba122 by Combined Magneto-optical Imaging and Finite-element Modeling
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
Shota Ishiwata, Sunseng Pyon, Tsuyoshi Tamegai, Mark D. Ainslie, Akiyasu Yamamoto
Macroscopic current uniformity in a (Ba,K)Fe2As2 bulk sample produced by a process that demonstrated high trapped magnetic fields was evaluated through a comparative experimental and modeling approach. The bulk sample, with a well-defined square geometry, exhibited ideal roof-top patterns in magneto-optical (MO) images. Comparison of the magnetic moment, MO images, and finite element modeling results showed good agreement for the critical current density, suggesting that the supercurrent circulates uniformly throughout the sample on the order of MO resolution. These results highlight the importance of enhancing flux pinning strength and microstructural control at the submicron and grain boundary scale in iron-based superconducting polycrystalline materials.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
8 pages, 6 figures
Supercond. Sci. Technol. 38 065014 (2025)
Nucleation kinetics in phase transformations with spatially correlated nuclei
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Phase transitions ruled by nucleation and growth can occur by nonrandom arrangement of nuclei. This is verified, for instance, in thin film growth at solid surfaces by vapor condensation or by electrodeposition where, around each nucleus, a depletion zone of reactants sets up within which nucleation is prevented. In this contribution, a theoretical approach for the kinetics of phase transition with spatially correlated nuclei by progressive nucleation is developed. The work focuses on the rate of formation of the actual nuclei, a quantity that is necessary for describing the transformation kinetics. The approach is based on correlation functions and applied to treat hard-sphere interaction between nuclei. Computations have been performed for 2D and 3D growths by truncation of the series expansion in correlation functions up to second order terms. It is shown that the nucleation kinetics undergoes a transition from a typical Random Sequential Adsorption (RSA) behavior to one that is like the Kolmogorov-Johnson-Mehl-Avrami (KJMA) kinetics. The time evolution of the volume fraction of the new phase is found to depend slightly on correlation radius. Such behavior is explained by the partial balancing between the reduction in nucleation density and the decrease in impingement events, which have opposite effects on the kinetics.
Statistical Mechanics (cond-mat.stat-mech), Materials Science (cond-mat.mtrl-sci)
24 pages, 13 figures
Ultrafast interband transitions in nanoporous gold metamaterial
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Tlek Tapani, Jonas M. Pettersson, Nils Henriksson, Erik Zäll, Nils V. Hauff, Lakshmi Das, Gianluca Balestra, Massimo Cuscunà, Aitor De Andrés, Tommaso Giovannini, Denis Garoli, Nicolò Maccaferri
Nanoporous metals have emerged as promising functional architectures due to their tunable optical and electronic properties, high surface areas, and versatile use in real-life applications such as sensing, catalysis, and biomedicine. While the optical and morphological properties of nanoporous metals have been extensively studied, their electronic properties at ultrafast timescales remain largely unexplored. Here, we study the transient response of a nanoporous gold metamaterial and compare it with the ultrafast dynamics of a continuous gold film. We unravel that the nanoporous sample supports lower energy interband transitions, due to a much higher electron temperature in the nanoporous material, which causes an enhanced redistribution of electron density around the Fermi level. The experimental results are consistent with the two-temperature model, which highlights the role of nanoscale porosity in enabling the more efficient generation of hot carriers, thus allowing lower energy photons to induce interband transitions. Our findings demonstrate that nanoporosity affects fundamental ultrafast electronic processes and introduces this platform as temporal metamaterial allowing the emergence of tunable electronic properties not supported by the bulk counterpart. Furthermore, we present new insights into ultrafast electronic properties of nanoporous metals, which can impact several areas, from photochemistry and catalysis to energy harvesting and opto-electronics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Andreev spin qubit protected by Franck-Condon blockade
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
P. D. Kurilovich, T. Vakhtel, T. Connolly, C. G. L. Bøttcher, B. van Heck
Andreev levels localized in a weak link between two superconductors can trap a superconducting quasiparticle. If there is a spin-orbit coupling in the link, the spin of the quasiparticle couples to the Josephson current. This effect can be leveraged to control and readout the spin of the quasiparticle thus using it as a qubit. One of the factors limiting the performance of such an Andreev spin qubit is spin relaxation. Here, we theoretically demonstrate that the relaxation lifetime can be enhanced by utilizing the coupling between the Andreev spin and the supercurrent in a transmon circuit. The coupling ensures that the flip of the quasiparticle spin can only happen if it is accompanied by the excitation of multiple plasmons, as dictated by the Frank-Condon principle. This blocks spin relaxation at temperatures small compared to plasmon energy.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 pages, 3 figures
Diffusion model for analyzing quantum fingerprints in conductance fluctuation
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Naoto Yokoi, Yuki Tanaka, Yukito Nonaka, Shunsuke Daimon, Junji Haruyama, Eiji Saitoh
A conditional diffusion model has been developed to analyze intricate conductance fluctuations called universal conductance fluctuations or quantum fingerprints appearing in quantum transport phenomena. The model reconstructs impurity arrangements and quantum interference patterns in nanometals by using magnetoconductance data, providing a novel approach to analyze complex data based on machine learning. In addition, we visualize the attention weights in the model, which efficiently extract information on the non-local correlation of the electron wave functions, and the score functions, which represent the force fields in the wave-function space.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
6 pages, 5 figures
Quantum Monte Carlo study of artificial triangular graphene quantum dots
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
E. Bulut Kul, Gökhan Öztarhan, M. N. Çınar, A. D. Güçlü
We investigate the magnetic phases of triangular graphene quantum
dots (TGQDs) with zigzag edges using variational and quantum Monte
Carlo methods. These systems serve as quantum simulators for
bipartite lattices with broken sublattice symmetry, providing a
platform to study the extended Hubbard model’s emergent magnetic
phenomena, including Lieb’s magnetism at half-filling, edge
depolarization upon single-electron addition, and Nagaoka
ferromagnetism. Our non-perturbative quantum Monte Carlo simulations,
performed for lattices of up to 61 sites, reveal that TGQDs
transition from metallic to insulating regimes as a function of site
radius size, while retaining edge-polarized ground states at
half-filling. Notably, edge depolarization occurs upon
single-electron doping in both metallic and insulating phases,
contrasting with the Nagaoka ferromagnetism observed in hexagonal
armchair geometries.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 5 figures
Site-resolved magnon and triplon dynamics on a programmable quantum dot spin ladder
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Pablo Cova Fariña, Daniel Jirovec, Xin Zhang, Elizaveta Morozova, Stefan D. Oosterhout, Stefano Reale, Tzu-Kan Hsiao, Giordano Scappucci, Menno Veldhorst, Lieven M. K. Vandersypen
Quasi-particle dynamics in interacting systems in the presence of disorder challenges the notion of internal thermalization, but proves difficult to investigate theoretically for large particle numbers. Engineered quantum systems may offer a viable alternative, as witnessed in experimental demonstrations in a variety of physical platforms, each with its own capabilities and limitations. Semiconductor gate-defined quantum dot arrays are of particular interest since they offer both a direct mapping of their Hamiltonian to Fermi-Hubbard and Heisenberg models and the in-situ tunability of (magnetic) interactions and onsite potentials. In this work, we use an array of germanium quantum dots to simulate the dynamics of both single-spin excitations (magnons) and two-spin excitations (triplons). We develop a methodology that combines digital spin qubit operations for state preparation and readout with analog evolution under the full system Hamiltonian. Using these techniques, we can reconstruct quantum walk plots for both magnons and triplons, and for various configurations of Heisenberg exchange couplings. We furthermore explore the effect of single-site disorder and its impact on the propagation of spin excitations. The obtained results can provide a basis for simulating disorder-based solid-state phenomena such as many-body localization.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
Ramanujan, Landau and Casimir, divergent series: a physicist point of view
New Submission | Other Condensed Matter (cond-mat.other) | 2025-06-11 20:00 EDT
It is a popular paradoxical exercise to show that the infinite sum of positive integer numbers is equal to -1/12, sometimes called the Ramanujan sum. Here we propose a qualitative approach, much like that of a physicist, to show how the value -1/12 can make sense and, in fact, appears in certain physical quantities where this type of summation is involved. At the light of two physical examples, taken respectively from condensed matter – the Landau diamagnetism – and quantum electrodynamics – the Casimir effect – that illustrate this strange sum, we present a systematic way to extract this Ramanujan term from the infinity.
Other Condensed Matter (cond-mat.other), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
14 pages, 6 figures, submitted to C. R. Acad. Sci. Paris
Light-induced localized vortices in multicomponent Bose-Einstein condensates
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-11 20:00 EDT
Y. Braver, D. Burba, S. S. Nair, G. Žlabys, E. Anisimovas, Th. Busch, G. Juzeliūnas
We study continuous interaction of a trapped two-component Bose-Einstein condensate with light fields in a $ \Lambda$ -type configuration. Using light beams with orbital angular momentum, we theoretically show how to create a stable, pinned vortex configuration, where the rotating component is confined to the region surrounded by the second, non-rotating component. The atoms constituting this vortex can be localized in volumes much smaller than the volume occupied by the second component. The position of the vortex can be robustly changed by moving the laser beams as long as the beam movement speed is below the speed of sound.
Quantum Gases (cond-mat.quant-gas)
11 pages, 6 figures
Non-Abelian Gauge Effect for 2-D Non-Hermitian Hatano-Nelson Model in Cylinder Type
New Submission | Other Condensed Matter (cond-mat.other) | 2025-06-11 20:00 EDT
Yiming Zhao, Yazhuang Miao, Yihang Xing, Tianhui Qiu, Hongyang Ma, Xiaolong Zhao
Non-Abelian gauge offers a powerful route to engineer novel topological phenomena. Here, we systematically investigate a two-dimensional (2-D) non-Hermitian Hatano-Nelson model incorporating SU(2) non-Abelian gauge, demonstrating the emergence of Hopf-link bulk braiding topology in the complex energy spectrum solely with x-direction nearest-neighbor couplings. Because of the limitations of exceptional point (EP) topology in fully capturing the rich non-Hermitian skin effect (NHSE) under non-Abelian influence, we introduce a novel polarization parameter derived from the generalized Brillouin zone (GBZ). This parameter quantitatively discerns left-, right-, and notably, bipolar skin modes, with its accuracy corroborated by directly encoding real-space eigenstate. Our findings reveal that non-Abelian gauge provides unprecedented influence over NHSE, compared with Abelian gauge and without gauge cases. Furthermore, we uncover unique characteristics of zero-imaginary-energy eigenstates at these topological boundaries, including pronounced degeneracy and bipolar localization which is unaffected by size effects, investigated via dynamical evolution and Inverse Participation Ratio (IPR). This work establishes a new paradigm for synthesizing and manipulating non-Hermitian topological phases driven by non-Abelian structures, opening avenues for topological engineering and holding promise for experimental realization in synthetic dimensional platforms.
Other Condensed Matter (cond-mat.other)
Frequency as a Clock: Synchronization and Intrinsic Recovery in Graphene Transistor Dynamics
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Victor Lopez-Richard, Igor Ricardo Filgueira e Silva, Gabriel L. Rodrigues, Kenji Watanabe, Takashi Taniguchi, Alisson R. Cadore
Hysteresis and memory effects in graphene field-effect transistors (GFETs) offer unique opportunities for neuromorphic computing, sensing, and memory applications, yet their physical origins remain debated due to competing volatile and nonvolatile interpretations. Here, we present a unified dynamic model that captures the essential physics of the GFET response under periodic gate modulation, accounting for both intrinsic relaxation processes and externally driven charge transfer. By modeling non-equilibrium carrier dynamics as a competition between injection and reabsorption rates, we uncover two distinct regimes: one governed by intrinsic, frequency-independent relaxation and another exhibiting frequency-locked behavior where the response is tied to the external drive. This distinction resolves apparent nonvolatile effects and explains loop invariance in floating-gate structures via displacement current-driven charge injection. Our framework predicts the evolution of the hysteresis loop shape, amplitude, and direction across a wide range of driving conditions, offering a versatile tool for interpreting experimental results and guiding the design of next-generation graphene-based electronic systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 5 figures
Gate Tunable Room-temperature Mott Insulator in Kagome compound Nb3Cl8
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-11 20:00 EDT
Qiu Yang, Min Wu, Jingyi Duan, Zhijie Ma, Lingxiao Li, Zihao Huo, Zaizhe Zhang, Kenji Watanabe, Takashi Taniguchi, Xiaoxu Zhao, Yi Chen, Youguo Shi, Wei Jiang, Kaihui Liu, Xiaobo Lu
The kagome lattice provides a playground to explore novel correlated quantum states due to the presence of flat bands in its electronic structure. Recently discovered layered kagome compound Nb3Cl8 has been proposed as a Mott insulator coming from the half-filled flat band. Here we have carried out systematic transport study to uncover the evidence of Mott insulator in Nb3Cl8 thin flakes. Bipolar semiconducting property with Fermi level close to conduction band has been revealed. We have further probed the chemical potential of Nb3Cl8 by tracing the charge neutrality point of the monolayer graphene proximate to Nb3Cl8. The gap of Nb3Cl8 flakes is approximately 1.10 eV at 100 K and shows pronounced temperature dependence, decreasing substantially with increasing temperature to ~0.63 eV at 300 K. The melting behavior of the gapped state is in consistent with theoretically proposed Mott insulator in Nb3Cl8. Our work has demonstrated Nb3Cl8 as a promising platform to study strongly correlated physics at relatively high temperature.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
14 pages, 4figures
Enhanced superconducting gap in the outer CuO$_2$ plane of the trilayer cuprate (Hg,Re)Ba$_2$Ca$_2$Cu$3$O${8+δ}$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
M. Horio, M. Miyamoto, Y. Mino, S. Ishida, B. Thiagarajan, C. M. Polley, C. H. Lee, T. Nishio, H. Eisaki, I. Matsuda
We report the first observation of a momentum-resolved superconducting gap in the Hg-based trilayer cuprate, which holds the highest record of superconducting transition temperature ($ T_\mathrm{c}$ ) at ambient pressure. By angle-resolved photoemission spectroscopy utilizing a micro-focused beam, clear quasiparticle dispersions originating from the inner and outer CuO$ 2$ planes (IP and OP, respectively) were separately identified. The magnitude of the superconducting gap for the IP was comparable to that of the Bi-based trilayer cuprate with a lower $ T\mathrm{c}$ . In contrast, the superconducting gap for the OP was significantly larger than that of the Bi-based one. While strong pairing in the IP has been highlighted as the key element of trilayer cuprates, the present results suggest that the enhanced pairing energy in the OP is essential for the highest $ T_\mathrm{c}$ at ambient pressure realized in the Hg-based trilayer cuprate.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
Accepted for publication in Phys. Rev. Lett
Full ab initio atomistic approach for morphology prediction of hetero-integrated crystals: A confrontation with experiments
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Sreejith Pallikkara Chandrasekharan, Sofia Apergi, Chen Wei, Federico Panciera, Laurent Travers, Gilles Patriarche, Jean-Christophe Harmand, Laurent Pedesseau, Charles Cornet
Here, we propose a comprehensive first-principle atomistic approach to predict the Wulff-Kaischew equilibrium shape of crystals heterogeneously integrated on a dissimilar material. This method uses both reconstructed surface and interface absolute energies, as determined by density functional theory, to infer the morphology and wetting properties of Volmer-Weber islands over the whole range of accessible chemical potentials. The predicted equilibrium shapes of GaP crystals heterogeneously grown on Si, are found to be in good agreements with experimental observations performed by Transmission Electron Microscopy. Such method provides a tool for optimization of hetero-structured, multifunctional and smart materials and devices.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph), Chemical Physics (physics.chem-ph), Computational Physics (physics.comp-ph)
20 pages, 3 figures
Atomic to mesoscale hierarchical structures and magnetic states in an anisotropic layered ferromagnet FePd2Te2
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Shuo Mi, Manyu Wang, Bingxian Shi, Songyang Li, Xiaoxiao Pei, Yanyan Geng, Shumin Meng, Rui Xu, Li Huang, Wei Ji, Fei Pang, Peng Cheng, Jianfeng Guo, Zhihai Cheng
Two-dimensional (2D) magnetic materials have predominantly exhibited easy-axis or easy-plane anisotropy and display a high sensitivity to the underlying crystal structure and lattice symmetry. Recently, an in-plane anisotropic 2D ferromagnet of FePd2Te2 has been discovered with intriguing structure and quasi-one-dimensional spin system. Here, we report a real-space investigation of its twinning structure and magnetic states using atomic/magnetic force microscopy (AFM/MFM) combined with scanning tunneling microscopy (STM). The atomic to mesoscale hierarchical structures with the orthogonal and corrugated compressive /tensile(C/T) regions are directly observed due to the intrinsic twinning-domain characteristic. The structure-related intact ferromagnetic (FM), field-induced polarized-FM states and their transitions are comparatively discussed at the mesoscale with the corresponding macroscopic magnetic measurements. Temperature- and field-dependent evolution of magnetic phase are further investigated at the FM and PM states, and summarized to obtain a unique H-T phase diagram of FePd2Te2. Our work provides key results for understanding the complicated magnetic properties of FePd2Te2, and suggests new directions for manipulating magnetic states through the atomic and mesoscale structure engineering.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Dissipationless tune-out trapping for a lanthanide-alkali quantum gas mixture
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-11 20:00 EDT
Alexandre De Martino, Florian Kiesel, Jonas Auch, Kirill Karpov, Christian Gross
Quantum gas mixtures offer a wide field of research, ranging from few-body physics of impurities to many-body physics with emergent long-range interactions and ultracold molecular gases. Achieving precision control of mixtures is much harder than for single-component gases and, consequently, the respective techniques are less developed. Here we report on a decisive step forward in this direction by realizing dissipationless and fully differential optical control of the motional degrees of freedom of one of the species without affecting the other. This is achieved in a novel Bose-Fermi mixture with extreme mass imbalance, erbium-166 and lithium-6. Our experiments pave the way to a new generation of precision many-body experiments with quantum gas mixtures with unprecedented long lifetimes and low temperatures.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph)
Aging of amorphous materials under cyclic strain
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Dor Shohat, Paul Baconnier, Itamar Procaccia, Martin van Hecke, Yoav Lahini
Amorphous materials driven away from equilibrium display a diverse repertoire of complex, history-dependent behaviors. One striking feature is a failure to return to equilibrium after an abrupt change in otherwise static external conditions. Instead, amorphous materials often exhibit physical aging: an ever-slowing, nonexponential relaxation that can span a huge range of timescales. Here we examine the aging behavior of three different amorphous materials subjected to slow periodic driving. The results reveal a generic aging phenomenon characterized by a logarithmic decay of dissipation per cycle. This observation is evaluated against several mesoscopic models of amorphous matter that successfully capture aging under static conditions: (i) a collection of noninteracting relaxation processes (ii) a noisy hysteron model with random pairwise interactions, and (iii) a structural model consisting of a random network of bi-stable elastic bonds. We find that only the latter model reproduces all experimental findings and relate its success to its persistent, slow exploration of a complex energy landscape with clear signatures of replica symmetry breaking. Thus, cyclic driving emerges as a simple yet powerful protocol to characterize amorphous materials, probe their complex energy landscapes, and distinguish between different models.
Soft Condensed Matter (cond-mat.soft)
13 pages, 7 figures
Hydrogen diffusion in ceria: solid state NMR, combined scattering and spectroscopic studies, and ab initio calculations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Zhichao Zhu, Xin Li, Ziru Ma, Yuanhua Xia, Ruizhi Qiu, Baijiang Lv, Guanyun Yan, Jianrong Zeng, Long Yang, Jianbo Ma, Benqiong Liu, Guangai Sun
Ceria has been extensively studied since it has many applications in diverse research fields. However, the mechanism of the hydrogen dynamics, especially the diffusion kinetics on a microscopic level is still unclear as the experimental data has been very limited. In this work, the CeO$ _2$ -H interaction has been comprehensively studied by a combination of $ ^1$ H NMR transverse relaxation time ($ T_2$ ) measurement, neutron powder diffraction, quasi-elastic neutron scattering (QENS), X-ray total scattering, and ab initio calculations. Based on QENS measurements, the first direct evidence for hydrogen jump diffusions of the Chudley-Elliot type in the bulk ceria has been given, with a jump distance of ~3.98 angstrom. The theoretically calculated activation energy barriers $ E_a$ for hydrogen diffusion are relatively low (less than 0.1 eV), further supporting that such hopping can readily occur. A larger barrier value of $ E_a$ ~0.2 eV is directly estimated by $ T_2$ NMR data, suggesting possible slower hydrogen dynamics with the pre-exponential factor $ D_0$ of diffusion coefficient ~10$ ^{-11}$ m$ ^2/$ s.
Materials Science (cond-mat.mtrl-sci)
10 pages, 9 figures
Imaging the indirect-to-direct band-gap crossover in PbI2
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
M. Rosmus (1), A. Antezak (1), A. Ptok (2), F. Fortuna (1), C. P. Sonny Tsotezem (1), E. M. Staicu Casagrande (1), A. Momeni (1), A. Ouvrard (1), C. Bigi (3), M. Zonno (3), A. Ouerghi (4), H. Khemliche (1), A. F. Santander-Syro (1), E. Frantzeskakis (1) ((1) Universite Paris-Saclay, CNRS, Institut des Sciences Moleculaires d’Orsay, 91405, Orsay, France, (2) Institute of Nuclear Physics, Polish Academy of Sciences, W. E. Radzikowskiego 152, PL-31342 Krakow, Poland, (3) SOLEIL Synchrotron, L’Orme des Merisiers, Departementale 128, 91190, Saint-Aubin, France, (4) Universite Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France)
The nature of the band-gap in PbI2 (i.e. direct or indirect) is crucial for its applications. Here we directly image, using angle-resolved photoemission spectroscopy, its thickness-dependent crossover from an indirect to a direct band-gap. We experimentally probe a large shift of the valence band maximum towards the center of the Brillouin zone, when the thickness of PbI2 films is greater than a monolayer. Our experimental results, accompanied by density functional theory calculations, suggest that the band-gap crossover is driven by interlayer interactions and the hybridization of iodine pz orbitals. These findings demonstrate the tunable electronic properties of PbI2, highlighting its potential for applications in optoelectronics.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Ferromagnetic Two-dimensional Electron Gases with Magnetic Doping and Proximity Effects
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Zixin Fan, Jiale Chen, Qiangtao Sui, Haoming Ling, Zihao Wang, Lingyuan Kong, Dingyi Li, Fang Yang, Run Zhao, Hanghui Chen, Pan Chen, Yan Liang, Jiandi Zhang
The advent of magnetic two-dimensional electron gases (2DEGs) at oxide interfaces has provided new opportunities in the field of spintronics. The enhancement of magnetism in 2DEGs at oxide interfaces continues to be a significant challenge, as exemplified by the relatively weak magnetism observed in the classical LaAlO3/SrTiO3 interface. Here, we present ferromagnetic (FM) 2DEGs at the interface fabricated between the FM insulator EuTiO3 (ETO) and the strong spin-orbit coupled (SOC) perovskite insulator KTaO3 (KTO). With the combined effects of magnetic atom doping and magnetic proximity from ETO films, the coercive field of 2DEGs can be significantly enhanced. Magnetoresistance (MR) curve with a high coercive field of 1000 Oe has been observed, in conjunction with a temperature-dependent unambiguous hysteresis loop in the anomalous Hall effect (AHE). Furthermore, within the 2DEGs, we have identified a synergetic interplay between magnetic scattering and the weak antilocalization (WAL) effect on transport. This study provides fresh insights into the formation of FM 2DEGs at ETO/KTO interfaces, and introduce an innovative pathway for creating high-performance magnetic 2DEGs at oxide interfaces.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
21 pages and 5 figures
Phys. Rev. B 111, 235415 (2025)
Crystal Nucleation in Eutectic Al-Si Alloys by Machine-Learned Molecular Dynamics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Solidification control is crucial in manufacturing technologies, as it determines the microstructure and, consequently, the performance of the final product. Investigating the mechanisms occurring during the early stages of nucleation remains experimentally challenging as it initiates on nanometer length and sub-picoseconds time scales. Large scale molecular dynamics simulations using machine learning interatomic potential with quantum accuracy appears the dedicated approach to complex, atomic level, multidimensional mechanisms with local symmetry breaking. A potential trained on a high-dimensional neural network on density functional theory-based ab initio molecular dynamics (AIMD) trajectories for liquid and undercooled states for Al-Si binary alloys enables us to study the nucleation mechanisms occurring at the early stages from the liquid phase near the eutectic composition. Our results indicate that nucleation starts with Al in hypoeutectic conditions and with Si in hypereutectic conditions. Whereas Al nuclei grow in a globular shape, Si ones grow with polygonal faceting, whose underlying mechanisms are further discussed.
Materials Science (cond-mat.mtrl-sci)
Main : 10 pages including references with 8 figures. Supplement : 10 pages with 9 figures. Our dataset together with the Machine Learning Interatomic Potential are available in : this https URL
Phonon- and magnon-mediated decoherence of a magnonic qubit
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
Vemund Falch, Arne Brataas, Jeroen Danon
We investigate the decoherence of magnonic qubits in small ferromagnetic insulators and compute the relaxation and dephasing rates due to magnon-phonon and magnon-magnon interactions. We combine a Bloch–Redfield description with Keldysh non-equilibrium field theory to find explicit expressions for the rates. For a quadratic dispersion and assuming a uniform mode defines the qubit, we find that decay into two phonons is the only allowed relaxation process at zero temperature. The low resonance frequency and heavy unit cell strongly suppress this process in yttrium-iron-garnet. We also find that the dephasing rate scales with the inverse of size and damping of the magnet, and could become large for small and clean magnets. Our calculation thus provides additional insight into the viability of magnon-based quantum devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
14 pages, 5 figures
Cavity-Mediated Gas-Liquid Transition
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-11 20:00 EDT
We study the gas-liquid transition in a binary Bose-Einstein condensate, where the two Zeeman-shifted hyperfine spin components are coupled by cavity-assisted Raman processes. Below a critical Zeeman field, the cavity becomes superradiant for an infinitesimally small pumping strength, where the enhanced superradiance is facilitated by the simultaneous formation of quantum droplet, a self-bound liquid phase stabilized by quantum fluctuations. Above the critical Zeeman field, the gas-liquid transition only takes place after the system becomes superradiant at a finite pumping strength. As the back action of the gas-liquid transition, the superradiant cavity field undergoes an abrupt jump at the first-order transition point. Furthermore, as a result of the fixed density ratio of the quantum droplet, the cavity field exhibits a linear scaling with the pumping strength in the liquid phase. These features serve as prominent signals for the cavity-mediated gas-liquid transition and coexistence, which derive from the interplay of Zeeman field, cavity-assisted spin mixing, and quantum fluctuations.
Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
A multi-physics model for dislocation driven spontaneous grain nucleation and microstructure evolution in polycrystals
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-11 20:00 EDT
Izzet Tarik Tandogan, Michael Budnitzki, Stefan Sandfeld
The granular microstructure of metals evolves significantly during thermomechanical processing through viscoplastic deformation and recrystallization. Microstructural features such as grain boundaries (GBs), subgrains, localized deformation bands, and non-uniform dislocation distributions critically influence grain nucleation and growth during recrystallization. Traditionally, modeling this coupled evolution involves separate, specialized frameworks for mechanical deformation and microstructural kinetics, typically used in a staggered manner. Nucleation is often introduced ad hoc, with nuclei seeded at predefined sites based on criteria like critical dislocation density, stress or strain. This is a consequence of the inherent limitations of the staggered approach, where newly formed GBs or grains have to be incorporated with additional processing. In this work, we propose a unified, thermodynamically consistent field theory that enables spontaneous nucleation driven by stored dislocations at GBs. The model integrates Cosserat crystal plasticity with the Henry-Mellenthin-Plapp orientation phase field approach, allowing the simulation of key microstructural defects, as well as curvature- and stored energy-driven grain boundary migration. The unified approach enables seamless identification of GBs that emerge from deformation and nucleation. Nucleation is activated through a coupling function that links dislocation-related free energy contributions to the phase field. Dislocation recovery occurs both at newly formed nuclei and behind migrating GBs. The model’s capabilities are demonstrated using periodic bicrystal and polycrystal simulations, where mechanisms such as strain-induced boundary migration, subgrain growth, and coalescence are captured. The proposed spontaneous nucleation mechanism offers a novel addition to the capabilities of phase field models for recrystallization simulation.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
35 pages, 18 figures, submitted to Journal of the Mechanics and Physics of Solids
Packing3D: An Open-Source Analytical Framework for Computing Packing Density and Mixing Indices Using Partial Spherical Volumes
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Freddie Barter, Christopher R. K. Windows-Yule
Accurate quantification of local packing density and mixing in simulations of particulate systems is essential for many industrial applications. Traditional methods which simply count the number of particle centres within a given volume of space (cell) introduce discontinuities at cell boundaries, leading to unreliable measurement of packing density. We introduce this http URL, an open-source Julia package providing analytic, partial-volume calculations for spheres intersecting Cartesian and cylindrical meshes. Our goals were to (1) eliminate boundary-artifact jumps, (2) maintain high throughput on large datasets, and (3) deliver standard mixing metrics via a unified API. We derive closed-form solutions for single, double and triple spherical-cap intersections, plus sphere-cylinder overlaps. A short-circuit bounding-sphere test shortens computations: fully inside or outside spheres are handled in $ \mathcal{O}(1)$ time, and only near-boundary spheres invoke the analytic kernels. We implement efficient mesh-generation routines, principal-cell indexing, and data-splitting functions for time-series analyses. Performance and accuracy were validated against simple cubic and face-centered cubic lattices and via boundary-shift continuity tests. this http URL converges exactly to theoretical lattice densities, eliminates discontinuities at sub-particle resolution, and processes up to $ 10^8$ sphere-cell intersections per second in single-threaded Julia with linear scaling in particle count. Memory usage remains modest (40 B per particle, 48 B per cell). this http URL provides researchers with continuous, reproducible volume-fraction fields and robust mixing indices at high performance, facilitating sensitivity analyses and optimization in granular process engineering. The package is freely available at this https URL
Soft Condensed Matter (cond-mat.soft), Mathematical Physics (math-ph)
11 pages, 5 figures. GitHub repository for the package available at: this https URL
Strain dependent viscous response describes the mechanics of cohesionless soft granular materials
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Chandan Shakya, Luca Placidi, Anil Misra, Lars Kool, Anke Lindner, Jasper van der Gucht, Joshua A. Dijksman
Granular materials are ubiquitous in nature and are used extensively in daily life and in industry. The modeling of these materials remains challenging; therefore, finding models with acceptable predictive accuracy that at the same time also reflect the complexity of the granular dynamics is a central research theme in the field. Soft particle packings present additional modeling challenges, as it has become clear that soft particles also have particle-level relaxation timescales that affect the packing behavior. We construct a simple one-dimensional, one-timescale model that replicates much of the essence of compressed hydrogel packing mechanics. We verify the model performance against both 3D and 2D packings of hydrogel particles, under both controlled strain and stress deformation conditions. We find that the modification of a Standard Linear Solid model with a strain dependent prefactor for the relaxation captures the time-history and rate dependence, as well as the necessary absence of cohesion effectively. We also indicate some directions of future improvement of the modeling.
Soft Condensed Matter (cond-mat.soft)
13 pages, 6 figures
Order-by-disorder in magnets with frustrated spin interactions – classical and large-$S$ limits via the spin functional integral
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-11 20:00 EDT
We investigate spin systems with extensive degeneracies in the classical ground states due to anisotropic frustrated spin interactions, where the degeneracy is not protected by symmetry. Using spin functional integration, we study the lifting of the degeneracies by fluctuations called order-by-disorder (ObD), and the associated gap in the spin-wave spectrum. It is shown that ObD corresponds to gradient-dependent anisotropic interactions of the pseudo-Goldstone modes, which vanish for a classical uniform spin configuration. Fluctuations generate a gradient-independent effective potential which determines the ground state and the pseudo-Goldstone gap. Furthermore, we recover previous predictions for the pseudo-Goldstone gap in type-I and II ObD with two-spin interactions in the large spin-$ S$ limit or the classical small temperature limit, by computing the gap explicitly for the type-II cubic compass model and the type-I square compass model. We show that these two limits correspond to the one-loop approximation for the effective potential. We also discuss other types of order by disorder due to $ m$ -spin interactions where $ m>2$ .
Strongly Correlated Electrons (cond-mat.str-el)
18 pages, 3 figures
Identifying vortex lattice in type-II superconductors via the dynamic magnetostrictive effect
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
Peipei Lu, Mengju Yuan, Jing Zhang, Qiang Gao, Shuang Liu, Yugang Zhang, Shipeng Shen, Long Zhang, Jun Lu, Xiaoyuan Zhou, Mingquan He, Aifeng Wang, Yang Li, Wenshan Hong, Shiliang Li, Huiqian Luo, Xingjiang Zhou, Xianhui Chen, Young Sun, Yisheng Chai
In type-I superconductors, zero electrical resistivity and perfect diamagnetism define two fundamental criteria for superconducting behavior. In contrast, type-II superconductors exhibit more complex mixed-state physics, where magnetic flux penetrates the material above the lower critical field Hc1 in the form of quantized vortices, each carrying a single flux quantum. These vortices form a two-dimensional lattice which persists up to another irreversible field (Hirr) and then melts into a dissipative liquid phase. The vortex lattice is fundamental to the magnetic and electrical properties of type-II superconductors, a third definitive criterion-beyond resistivity and magnetization-for identifying this phase has remained elusive. Here, we report the discovery of a dynamic magnetostrictive effect, wherein the geometry of the superconductor oscillates only under an applied alternating magnetic field due to the disturbance of the vortex lattice. This effect is detected by a thin piezoelectric transducer, which converts the excited geometric deformation into an in-phase ac voltage. Notably, we find a direct and nearly linear relationship between the signal amplitude and the vortex density in lattice across several representative type-II superconductors. In the vortex liquid phase above Hirr, the signal amplitude rapidly decays to zero near the upper critical field (Hc2), accompanied by a pronounced out-of-phase component due to enhanced dissipation. This dynamic magnetostrictive effect not only reveals an unexplored magnetoelastic property of the vortex lattice but also establishes a fundamental criterion for identifying the type-II superconductors.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
27 pages, 8 figures, submitted
Brownian motion with stochastic energy renewals
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Ion Santra, Kristian Stølevik Olsen
We investigate the impact of intermittent energy injections on a Brownian particle, modeled as stochastic renewals of its kinetic energy to a fixed value. Between renewals, the particle follows standard underdamped Langevin dynamics. For energy renewals occurring at a constant rate, we find non-Boltzmannian energy distributions that undergo a shape transition driven by the competition between the velocity relaxation timescale and the renewal timescale. In the limit of rapid renewals, the dynamics mimics one-dimensional run-and-tumble motion, while at finite renewal rates, the effective diffusion coefficient exhibits non-monotonic behavior. To quantify the system’s departure from equilibrium, we derive a modified fluctuation-response relation and demonstrate the absence of a consistent effective temperature. The dissipation is characterized by deviations from equilibrium-like response, captured via the Harada-Sasa relation. Finally, we extend the analysis to non-Poissonian renewal processes and introduce a dimensionless conversion coefficient that quantifies the thermodynamic cost of diffusion.
Statistical Mechanics (cond-mat.stat-mech)
Nonequilibrium fluctuation-response relations for state-current correlations
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Krzysztof Ptaszynski, Timur Aslyamov, Massimiliano Esposito
Recently, novel exact identities known as Fluctuation-Response Relations (FRRs) have been derived for nonequilibrium steady states of Markov jump processes. These identities link the fluctuations of state or current observables to a combination of responses of these observables to perturbations of transition rates. Here, we complement these results by deriving analogous FRRs applicable to mixed covariances of one state and one current observable. We further derive novel Inverse FRRs expressing individual state or current response in terms of a combination of covariances rather than vice versa. Using these relations, we demonstrate that the breaking of the Onsager symmetry can occur only in the presence of state-current correlations. On the practical side, we demonstrate the applicability of FRRs for simplifying calculations of fluctuations in large Markov networks, we use them to explain the behavior of fluctuations in quantum dot devices or enzymatic reaction schemes, and discuss their potential relevance for model inference.
Statistical Mechanics (cond-mat.stat-mech)
10 pages, 6 figures. Companion paper to arXiv:2412.10233
Experimental evidence of the topological obstruction in twisted bilayer graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-11 20:00 EDT
F. Mesple, P. Mallet, C. Dutreix, G. Lapertot, J-Y. Veuillen, V. T. Renard
The rich physics of magic angle twisted bilayer graphene (TBG) results from the Coulomb interactions of electrons in flat bands of non-trivial topology. While the bands’ dispersion is well characterized, accessing their topology remains an experimental challenge. Recent measurements established the local density of states (LDOS) as a topological observable. Here, we use scanning tunnelling microscopy to investigate the LDOS of TBG near a defect. We observe characteristic patterns resulting from the Dirac cones having the same chirality within a moiré valley. At higher energies, we observe the Lifshitz transition associated with the Dirac cones mixing. Our measurements provide a full characterization of TBG’s band structure, confirming the main features of the continuum model including the renormalization of the Fermi velocity, the role of emergent symmetries and the topological obstruction of the wavefunctions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 pages, 3 figures, supplements on request
Thermodynamics of microphase separation in a swollen, strain-stiffening polymer network
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-11 20:00 EDT
Carla Fernández-Rico, Robert W. Style, Stefanie Heyden, Shichen Wang, Peter D. Olmsted, Eric R. Dufresne
Elastic MicroPhase Separation (EMPS) provides a simple route to create soft materials with homogeneous microstructures by leveraging the supersaturation of crosslinked polymer networks with liquids. At low supersaturation, network elasticity stabilizes a uniform mixture, but beyond a critical threshold, metastable microphase-separated domains emerge. While previous theories have focused on describing qualitative features about the size and morphology of these domains, they do not make quantitative predictions about EMPS phase diagrams. In this work, we extend Flory-Huggins theory to quantitatively capture EMPS phase diagrams by incorporating strain-stiffening effects. This model requires no fitting parameters and relies solely on independently measured solubility parameters and large-deformation mechanical responses. Our results reveal that strain-stiffening enables metastable microphase separation within the swelling equilibrium state and why the microstructures can range from discrete droplets to bicontinuous networks. This works highlights the critical role of nonlinear elasticity in controlling phase-separated morphologies in polymer gels.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
Giant transverse magnetic fluctuations at the edge of re-entrant superconductivity in UTe$_{2}$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-11 20:00 EDT
Valeska Zambra, Amit Nathwani, Muhammad Nauman, Sylvia K. Lewin, Corey E. Frank, Nicholas P. Butch, Arkady Shekhter, B. J. Ramshaw, K. A. Modic
UTe$ _{2}$ exhibits the remarkable phenomenon of re-entrant superconductivity, whereby the zero-resistance state reappears above 40 tesla after being suppressed with a field of around 10 tesla. One potential pairing mechanism, invoked in the related re-entrant superconductors UCoGe and URhGe, involves transverse fluctuations of a ferromagnetic order parameter. However, the requisite ferromagnetic order - present in both UCoGe and URhGe - is absent in UTe$ _{2}$ , and magnetization measurements show no sign of strong fluctuations. Here, we measure the magnetotropic susceptibility of UTe$ _{2}$ across two field-angle planes. This quantity is sensitive to the magnetic susceptibility in a direction transverse to the applied magnetic field - a quantity that is not accessed in conventional magnetization measurements. We observe a very large decrease in the magnetotropic susceptibility over a broad range of field orientations, indicating a large increase in the transverse magnetic susceptibility. The three superconducting phases of UTe$ _{2}$ , including the high-field re-entrant phase, surround this region of enhanced susceptibility in the field-angle phase diagram. The strongest transverse susceptibility is found near the critical end point of the high-field metamagnetic transition, suggesting that quantum critical fluctuations of a field-induced magnetic order parameter may be responsible for the large transverse susceptibility, and may provide a pairing mechanism for field-induced superconductivity in UTe$ _{2}$ .
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
Tuning the the fundamental periodicity of the current-phase relation in multiterminal diffusive Josephson junctions
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-11 20:00 EDT
Conventional superconductor/insulator/superconductor (SIS) Josephson junctions, devices where two superconductors are separated by a tunnel barrier are technologically important as elements in quantum circuits, particularly with their key role in superconducting qubits. An important characteristic of Josephson junctions is the relation between the supercurrent Is and the phase difference {\phi} between them. For SIS junctions, the current-phase relation is sinusioidal and 2{\pi} periodic. Other types of Josephson junctions, where the material between the superconductors is a weak link or a normal metal (N) may have non-sinusoidal current-phase relations that are still 2{\pi} periodic. We show here that a multi-terminal diffusive SNS Josephson junction with 4 superconducting contacts can show a current phase relation between two of the contacts that is a superposition of 2{\pi} and 4{\pi} periodic components whose relative strength is controlled by the phase difference between the other two contacts, becoming 2{\pi} or 4{\pi} periodic for certain values of this phase difference. This tunability might have applications in tailoring the Hamiltonians of superconducting quantum circuits.
Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
Eigenstate Thermalization Hypothesis and Random Matrix Theory Universality in Few-Body Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Jiaozi Wang, Hua Yan, Robin Steinigeweg, Jochen Gemmer
In this paper, we study the Feingold-Peres model as an example, which is a well-known paradigm of quantum chaos. Using semiclassical analysis and numerical simulations, we study the statistical properties of observables in few-body systems with chaotic classical limits and the emergence of random matrix theory universality. More specifically, we focus on: 1) the applicability of the eigenstate thermalization hypothesis in few-body systems and the dependence of its form on the effective Planck constant and 2) the existence of a universal random matrix theory description of observables when truncated to a small microcanonical energy window. Our results provide new insights into the established field of few-body quantum chaos and help bridge it to modern perspectives, such as the general eigenstate thermalization hypothesis (ETH).
Statistical Mechanics (cond-mat.stat-mech), Chaotic Dynamics (nlin.CD)
13 pages, 14 figures
Mixed phases in feedback Ising models
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-11 20:00 EDT
Yi-Ping Ma, Ivan Sudakow, P. L. Krapivsky
We study mean-field Ising models whose coupling depends on the magnetization via a feedback function. We identify mixed phases (MPs) and show that they can be stable at zero temperature for sufficiently strong feedback. Moreover, stable MPs are always super-stable with perturbation decaying linearly in time. We argue that such feedback Ising models (FIMs) provide a useful framework for phase transformations between aligned phases via stable and unstable intermediate phases in multistable systems. We also analyze the dynamical behavior of FIMs driven by a time-varying magnetic field.
Statistical Mechanics (cond-mat.stat-mech), Dynamical Systems (math.DS)
7 pages, 3 figures
Discovery of a 1D edge mode in a Magnetic Topological semimetal
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-11 20:00 EDT
Avior Almoalem, Rebecca Chan, Brinda Kuthanazhi, Juan Scmidt, Jose A. Moreno, Hermann Suderow, Paul Canfield, Taylor L. hughes, Vidya Madhavan
In rare-earth monopnictides like NdBi, the interplay between magnetism and topology results in an extremely unusual topological semimetal phase which simultaneously hosts Weyl points with Fermi arcs as well as massive and massless Dirac cones. A central question in this class of materials is whether ferromagnetic surfaces with gapped Dirac cones can also host robust well-defined chiral edge states. In this study, we use spin-polarized scanning tunneling microscopy (SP-STM) and spectroscopy to investigate the correlation between the magnetic and topological properties of NdBi. By combining SP-STM imaging with quasiparticle interference, we identify distinct signatures of both antiferromagnetic and ferromagnetic surface terminations and correlate them with their respective band structures. Crucially, we demonstrate that step edges on the ferromagnetic surface which serve as magnetic domain walls host well-defined one-dimensional (1D) edge modes that vanish above the Néel temperature. Our findings position NdBi as a promising platform for further explorations of 1D chiral edge modes and future realizations of Majorana states in proximitized rare-earth monopnictides.
Strongly Correlated Electrons (cond-mat.str-el)