CMP Journal 2025-06-04
Statistics
Nature: 23
Nature Nanotechnology: 1
Nature Physics: 1
Physical Review Letters: 8
Physical Review X: 2
Review of Modern Physics: 1
arXiv: 51
Nature
Milli-spinner thrombectomy
Original Paper | Biomedical engineering | 2025-06-03 20:00 EDT
Yilong Chang, Shuai Wu, Qi Li, Benjamin Pulli, Darren Salmi, Paul Yock, Jeremy J. Heit, Ruike Renee Zhao
Clot-induced blockage in arteries or veins can cause severe medical conditions1. Mechanical thrombectomy is a minimally invasive technique used to treat ischaemic stroke, myocardial infarction, pulmonary embolism and peripheral vascular disease2,3,4 by removing clots through aspiration5, stent retriever6 or cutting mechanisms7. However, current mechanical thrombectomy methods fail to remove clots in 10-30% of patients8,9,10, especially in the case of large, fibrin-rich clots11. These methods can also rupture and fragment clots12, causing distal emboli and poor outcomes13. To overcome these challenges, we develop the milli-spinner thrombectomy, which uses a simple yet innovative mechanics concept to modify the clot’s microstructure, facilitating its removal. The milli-spinner works by mechanically densifying the clot’s fibrin network and releasing red blood cells through spinning-induced compression and shear forces. It can shrink the clot volume by 95% for easy and fast removal. In vitro tests in pulmonary and cerebral artery flow models and in vivo experiments in swine models demonstrate that the milli-spinner achieves ultrafast clot debulking and high-fidelity revascularization, outperforming aspiration thrombectomy. The milli-spinner thrombectomy directly modifies the clot microstructure to facilitate clot removal, improving mechanical thrombectomy success rates compared with current methods that rely on clot rupture or cutting. This approach offers a promising new direction for mechanical thrombectomy devices, especially for treating ischaemic stroke, pulmonary embolism and peripheral thrombosis.
Biomedical engineering, Mechanical engineering
Molecular gradients shape synaptic specificity of a visuomotor transformation
Original Paper | Molecular neuroscience | 2025-06-03 20:00 EDT
Mark Dombrovski, Yixin Zang, Giovanni Frighetto, Andrea Vaccari, HyoJong Jang, Parmis S. Mirshahidi, Fangming Xie, Piero Sanfilippo, Bryce W. Hina, Aadil Rehan, Roni H. Hussein, Pegah S. Mirshahidi, Catherine Lee, Aileen Morris, Mark A. Frye, Catherine R. von Reyn, Yerbol Z. Kurmangaliyev, Gwyneth M. Card, S. Lawrence Zipursky
How does the brain convert visual input into specific motor actions1,2? In Drosophila, visual projection neurons (VPNs)3,4 perform this visuomotor transformation by converting retinal positional information into synapse number in the brain5. The molecular basis of this phenomenon remains unknown. We addressed this issue in LPLC2 (ref. 6), a VPN type that detects looming motion and preferentially drives escape behaviour to stimuli approaching from the dorsal visual field with progressively weaker responses ventrally. This correlates with a dorsoventral gradient of synaptic inputs into and outputs from LPLC2. Here we report that LPLC2 neurons sampling different regions of visual space exhibit graded expression of cell recognition molecules matching these synaptic gradients. Dpr13 shapes LPLC2 outputs by binding DIP-ε in premotor descending neurons mediating escape. Beat-VI shapes LPLC2 inputs by binding Side-II in upstream motion-detecting neurons. Gain-of-function and loss-of-function experiments show that these molecular gradients act instructively to determine synapse number. These patterns, in turn, fine-tune the perception of the stimulus and drive the behavioural response. Similar transcriptomic variation within neuronal types is observed in the vertebrate brain7 and may shape synapse number via gradients of cell recognition molecules acting through both genetically hard-wired programs and experience.
Molecular neuroscience, Neural circuits, Neuronal development
A multidimensional distributional map of future reward in dopamine neurons
Original Paper | Learning algorithms | 2025-06-03 20:00 EDT
Margarida Sousa, Pawel Bujalski, Bruno F. Cruz, Kenway Louie, Daniel C. McNamee, Joseph J. Paton
Midbrain dopamine neurons (DANs) signal reward-prediction errors that teach recipient circuits about expected rewards1. However, DANs are thought to provide a substrate for temporal difference (TD) reinforcement learning (RL), an algorithm that learns the mean of temporally discounted expected future rewards, discarding useful information about experienced distributions of reward amounts and delays2. Here we present time-magnitude RL (TMRL), a multidimensional variant of distributional RL that learns the joint distribution of future rewards over time and magnitude. We also uncover signatures of TMRL-like computations in the activity of optogenetically identified DANs in mice during behaviour. Specifically, we show that there is significant diversity in both temporal discounting and tuning for the reward magnitude across DANs. These features allow the computation of a two-dimensional, probabilistic map of future rewards from just 450 ms of the DAN population response to a reward-predictive cue. Furthermore, reward-time predictions derived from this code correlate with anticipatory behaviour, suggesting that similar information is used to guide decisions about when to act. Finally, by simulating behaviour in a foraging environment, we highlight the benefits of a joint probability distribution of reward over time and magnitude in the face of dynamic reward landscapes and internal states. These findings show that rich probabilistic reward information is learnt and communicated to DANs, and suggest a simple, local-in-time extension of TD algorithms that explains how such information might be acquired and computed.
Learning algorithms, Reward
Integrated photonic source of Gottesman-Kitaev-Preskill qubits
Original Paper | Integrated optics | 2025-06-03 20:00 EDT
M. V. Larsen, J. E. Bourassa, S. Kocsis, J. F. Tasker, R. S. Chadwick, C. González-Arciniegas, J. Hastrup, C. E. Lopetegui-González, F. M. Miatto, A. Motamedi, R. Noro, G. Roeland, R. Baby, H. Chen, P. Contu, I. Di Luch, C. Drago, M. Giesbrecht, T. Grainge, I. Krasnokutska, M. Menotti, B. Morrison, C. Puviraj, K. Rezaei Shad, B. Hussain, J. McMahon, J. E. Ortmann, M. J. Collins, C. Ma, D. S. Phillips, M. Seymour, Q. Y. Tang, B. Yang, Z. Vernon, R. N. Alexander, D. H. Mahler
Building a useful photonic quantum computer requires robust techniques to synthesize optical states that can encode qubits. Gottesman-Kitaev-Preskill (GKP) states1 offer one of the most attractive classes of such qubit encodings, as they enable the implementation of universal gate sets with straightforward, deterministic and room temperature-compatible Gaussian operations2. Existing pioneering demonstrations generating optical GKP states3 and other complex non-Gaussian states4,5,6,7,8,9,10,11 have relied on free-space optical components, hindering the scaling eventually required for a utility-scale system. Here we use an ultra-low-loss integrated photonic chip fabricated on a customized multilayer silicon nitride 300-mm wafer platform, coupled over fibre with high-efficiency photon number resolving detectors, to generate GKP qubit states. These states show critical mode-level features necessary for fault tolerance, including at least four resolvable peaks in both p and q quadratures, and a clear lattice structure of negative Wigner function regions, in this case a 3 × 3 grid. We also show that our GKP states show sufficient structure to indicate that the devices used to make them could, after further reduction in optical losses, yield states for the fault-tolerant regime. This experiment validates a key pillar of bosonic architectures for photonic quantum computing2,12, paving the way for arrays of GKP sources that will supply future fault-tolerant machines.
Integrated optics, Photonic devices, Quantum optics, Qubits, Single photons and quantum effects
Maternal iron deficiency causes male-to-female sex reversal in mouse embryos
Original Paper | Cell lineage | 2025-06-03 20:00 EDT
Naoki Okashita, Ryo Maeda, Shunsuke Kuroki, Kyona Sasaki, Yoko Uno, Peter Koopman, Makoto Tachibana
Ferrous iron (Fe2+) is essential in all eukaryotic cells for various oxidoreductase reactions, including the demethylation of DNA and proteins. Histone demethylation is required for normal epigenetic regulation of the Y-chromosomal sex-determining gene Sry in developing gonads during male sex determination1,2. Here we investigate the potential connection between iron metabolism, histone demethylation and sex determination in mammals. We found that Fe2+-producing pathways are substantially activated in mouse embryonic gonads during the sex-determining period. Chelation of iron in cultured XY gonads reduced the level of KDM3A-mediated H3K9 demethylation of Sry, mostly abolished Sry expression and caused the gonads to express ovarian markers. In vivo, conditional deletion of the gene Tfrc–which is required for iron incorporation–in fetal XY gonadal somatic cells, or acute pharmaceutical suppression of available iron in pregnant mice, resulted in male-to-female gonadal sex reversal in a proportion of offspring, highlighting the pivotal role of iron metabolism in male sex determination. Finally, long-term feeding of pregnant mice with a low-iron diet, when combined with a heterozygous variant of Kdm3a that by itself has no observable effect, suppressed Sry expression and caused male-to-female sex reversal in some of the progeny, revealing a connection between maternal dietary iron and fetal developmental outcomes.
Cell lineage, Development, Epigenetics
Coordination environments of Pt single-atom catalysts from NMR signatures
Original Paper | Heterogeneous catalysis | 2025-06-03 20:00 EDT
Jonas Koppe, Alexander V. Yakimov, Domenico Gioffrè, Marc-Eduard Usteri, Thomas Vosegaard, Guido Pintacuda, Anne Lesage, Andrew J. Pell, Sharon Mitchell, Javier Pérez-Ramírez, Christophe Copéret
Supported metal catalysts that integrate atomically dispersed species with controlled structures lie at the forefront of catalytic materials design, offering exceptional control over reactivity and high metal utilization, approaching the precision of molecular systems1,2,3. However, accurately resolving the local metal coordination environments remains challenging, hindering the advancement of structure-activity relationships needed to optimize their design for diverse applications1,2. Although electron microscopy reveals atomic dispersion, conventional spectroscopic methods used in heterogeneous catalysis only provide average structural information. Here we demonstrate that 195Pt solid-state nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for characterizing atomically dispersed Pt sites on various supports, so called single-atom catalysts (SACs). Monte Carlo simulations allow the conversion of NMR spectra into SAC signatures that describe coordination environments with molecular precision, enabling quantitative assessment of Pt-site distribution and homogeneity. This methodology can track the influence of synthetic parameters, uncovering the impact of specific steps and support types, and can also monitor changes upon reaction. It offers critical insights for the reproducible development of SACs with targeted structures. Beyond SACs, this approach lays the foundation for studying more complex architectures, such as dual-atom or single-cluster catalysts, containing various NMR-active metals.
Heterogeneous catalysis, Organometallic chemistry, Surface spectroscopy
Observation of string breaking on a (2 + 1)D Rydberg quantum simulator
Original Paper | Atomic and molecular physics | 2025-06-03 20:00 EDT
Daniel González-Cuadra, Majd Hamdan, Torsten V. Zache, Boris Braverman, Milan Kornjača, Alexander Lukin, Sergio H. Cantú, Fangli Liu, Sheng-Tao Wang, Alexander Keesling, Mikhail D. Lukin, Peter Zoller, Alexei Bylinskii
Lattice gauge theories (LGTs) describe a broad range of phenomena in condensed matter and particle physics. A prominent example is confinement, responsible for bounding quarks inside hadrons such as protons or neutrons1. When quark-antiquark pairs are separated, the energy stored in the string of gluon fields connecting them grows linearly with their distance, until there is enough energy to create new pairs from the vacuum and break the string. Although these phenomena are ubiquitous in LGTs, simulating the resulting dynamics is a challenging task2. Here we report the observation of string breaking in synthetic quantum matter using a programmable quantum simulator based on neutral atom arrays3,4,5. We show that a (2 + 1)-dimensional LGT with dynamical matter can be efficiently implemented when the atoms are placed on a Kagome geometry6, with a local U(1) symmetry emerging from the Rydberg blockade7. Long-range Rydberg interactions naturally give rise to a linear confining potential for a pair of charges, allowing us to tune both their masses and the string tension. We experimentally probe string breaking in equilibrium by adiabatically preparing the ground state of the atom array in the presence of defects, distinguishing regions within the confined phase dominated by fluctuating strings or by broken string configurations. Finally, by harnessing local control over the atomic detuning, we quench string states and observe string-breaking dynamics exhibiting a many-body resonance phenomenon. Our work provides opportunities for exploring phenomena in high-energy physics using programmable quantum simulators.
Atomic and molecular physics, Particle physics, Quantum simulation
Ancient DNA reveals a two-clanned matrilineal community in Neolithic China
Original Paper | Anthropology | 2025-06-03 20:00 EDT
Jincheng Wang, Shi Yan, Zhenguang Li, Jinguo Zan, Yichao Zhao, Jin Zhao, Kui Chen, Xueye Wang, Ting Ji, Cheng Zhang, Tingyu Yang, Tianming Zhang, Rui Qiao, Meilin Guo, Zongyue Rao, Jiashuo Zhang, Guanbo Wang, Zhiyu Ran, Chen Duan, Fan Zhang, Yin Song, Xiaohong Wu, Ruth Mace, Bo Sun, Yuhong Pang, Yanyi Huang, Hai Zhang, Chao Ning
Studies of ancient DNA from cemeteries provide valuable insights into early human societies, and have strongly indicated patrilocality1,2,3,4,5,6,7,8,9,10. Here, we analysed ancient DNA alongside archaeological contexts and multiple stable isotopic data from 60 individuals in 2 separate cemeteries at the Fujia archaeological site in eastern China, dating between 2750 and 2500 bce. Our findings suggest the existence of an early-described matrilineal community in the Neolithic period, characterized by high endogamy and a population practicing millet agriculture near the coast. Evidence of intermarriage between individuals in the two cemeteries and the presence of both primary and secondary burials, organized strictly according to maternal clans, underscore a strong sense of social cohesion and identity at Fujia. Bayesian modelling of radiocarbon dates indicates that the two cemeteries were used for approximately 250 years, implying a stable matrilineal lineage spanning at least 10 generations. This study contributes to the ongoing debate in anthropology and archaeology11, not only suggesting the existence of a matrilineal society in early human history but also revealing a pair of Neolithic cemeteries organized around two matrilineal clans, furthering our understanding of the early evolution of human societies through kinship systems.
Anthropology, Archaeology, Population genetics, Social evolution
Visualizing dynamics of charges and strings in (2 + 1)D lattice gauge theories
Original Paper | Phase transitions and critical phenomena | 2025-06-03 20:00 EDT
T. A. Cochran, B. Jobst, E. Rosenberg, Y. D. Lensky, G. Gyawali, N. Eassa, M. Will, A. Szasz, D. Abanin, R. Acharya, L. Aghababaie Beni, T. I. Andersen, M. Ansmann, F. Arute, K. Arya, A. Asfaw, J. Atalaya, R. Babbush, B. Ballard, J. C. Bardin, A. Bengtsson, A. Bilmes, A. Bourassa, J. Bovaird, M. Broughton, D. A. Browne, B. Buchea, B. B. Buckley, T. Burger, B. Burkett, N. Bushnell, A. Cabrera, J. Campero, H.-S. Chang, Z. Chen, B. Chiaro, J. Claes, A. Y. Cleland, J. Cogan, R. Collins, P. Conner, W. Courtney, A. L. Crook, B. Curtin, S. Das, S. Demura, L. De Lorenzo, A. Di Paolo, P. Donohoe, I. Drozdov, A. Dunsworth, A. Eickbusch, A. Moshe Elbag, M. Elzouka, C. Erickson, V. S. Ferreira, L. Flores Burgos, E. Forati, A. G. Fowler, B. Foxen, S. Ganjam, R. Gasca, É. Genois, W. Giang, D. Gilboa, R. Gosula, A. Grajales Dau, D. Graumann, A. Greene, J. A. Gross, S. Habegger, M. Hansen, M. P. Harrigan, S. D. Harrington, P. Heu, O. Higgott, J. Hilton, H.-Y. Huang, A. Huff, W. Huggins, E. Jeffrey, Z. Jiang, C. Jones, C. Joshi, P. Juhas, D. Kafri, H. Kang, A. H. Karamlou, K. Kechedzhi, T. Khaire, T. Khattar, M. Khezri, S. Kim, P. Klimov, B. Kobrin, A. Korotkov, F. Kostritsa, J. Kreikebaum, V. Kurilovich, D. Landhuis, T. Lange-Dei, B. Langley, K.-M. Lau, J. Ledford, K. Lee, B. Lester, L. Le Guevel, W. Li, A. T. Lill, W. Livingston, A. Locharla, D. Lundahl, A. Lunt, S. Madhuk, A. Maloney, S. Mandrà, L. Martin, O. Martin, C. Maxfield, J. McClean, M. McEwen, S. Meeks, A. Megrant, K. Miao, R. Molavi, S. Molina, S. Montazeri, R. Movassagh, C. Neill, M. Newman, A. Nguyen, M. Nguyen, C.-H. Ni, K. Ottosson, A. Pizzuto, R. Potter, O. Pritchard, C. Quintana, G. Ramachandran, M. Reagor, D. Rhodes, G. Roberts, K. Sankaragomathi, K. Satzinger, H. Schurkus, M. Shearn, A. Shorter, N. Shutty, V. Shvarts, V. Sivak, S. Small, W. C. Smith, S. Springer, G. Sterling, J. Suchard, A. Sztein, D. Thor, M. Torunbalci, A. Vaishnav, J. Vargas, S. Vdovichev, G. Vidal, C. Vollgraff Heidweiller, S. Waltman, S. X. Wang, B. Ware, T. White, K. Wong, B. W. K. Woo, C. Xing, Z. Jamie Yao, P. Yeh, B. Ying, J. Yoo, N. Yosri, G. Young, A. Zalcman, Y. Zhang, N. Zhu, N. Zobrist, S. Boixo, J. Kelly, E. Lucero, Y. Chen, V. Smelyanskiy, H. Neven, A. Gammon-Smith, F. Pollmann, M. Knap, P. Roushan
Lattice gauge theories (LGTs)1,2,3,4 can be used to understand a wide range of phenomena, from elementary particle scattering in high-energy physics to effective descriptions of many-body interactions in materials5,6,7. Studying dynamical properties of emergent phases can be challenging, as it requires solving many-body problems that are generally beyond perturbative limits8,9,10. Here we investigate the dynamics of local excitations in a ({ {\mathbb{Z}}}_{2}) LGT using a two-dimensional lattice of superconducting qubits. We first construct a simple variational circuit that prepares low-energy states that have a large overlap with the ground state; then we create charge excitations with local gates and simulate their quantum dynamics by means of a discretized time evolution. As the electric field coupling constant is increased, our measurements show signatures of transitioning from deconfined to confined dynamics. For confined excitations, the electric field induces a tension in the string connecting them. Our method allows us to experimentally image string dynamics in a (2+1)D LGT, from which we uncover two distinct regimes inside the confining phase: for weak confinement, the string fluctuates strongly in the transverse direction, whereas for strong confinement, transverse fluctuations are effectively frozen11,12. We also demonstrate a resonance condition at which dynamical string breaking is facilitated. Our LGT implementation on a quantum processor presents a new set of techniques for investigating emergent excitations and string dynamics.
Phase transitions and critical phenomena, Quantum simulation
Old carbon routed from land to the atmosphere by global river systems
Original Paper | Carbon cycle | 2025-06-03 20:00 EDT
Joshua F. Dean, Gemma Coxon, Yanchen Zheng, Jack Bishop, Mark H. Garnett, David Bastviken, Valier Galy, Robert G. M. Spencer, Suzanne E. Tank, Edward T. Tipper, Jorien E. Vonk, Marcus B. Wallin, Liwei Zhang, Chris D. Evans, Robert G. Hilton
Rivers and streams are an important pathway in the global carbon cycle, releasing carbon dioxide (CO2) and methane (CH4) from their water surfaces to the atmosphere1,2. Until now, CO2 and CH4 emitted from rivers were thought to be predominantly derived from recent (sub-decadal) biomass production and, thus, part of ecosystem respiration3,4,5,6. Here we combine new and published measurements to create a global database of the radiocarbon content of river dissolved inorganic carbon (DIC), CO2 and CH4. Isotopic mass balance of our database suggests that 59 ± 17% of global river CO2 emissions are derived from old carbon (millennial or older), the release of which is linked to river catchment lithology and biome. This previously unrecognized release of old, pre-industrial-aged carbon to the atmosphere from long-term soil, sediment and geologic carbon stores through lateral hydrological routing equates to 1.2 ± 0.3 Pg C year-1, similar in magnitude to terrestrial net ecosystem exchange. A consequence of this flux is a greater than expected net loss of carbon from aged organic matter stores on land. This requires a reassessment of the fate of anthropogenic carbon in terrestrial systems and in global carbon cycle budgets and models.
Carbon cycle, Hydrology
Warming accelerates global drought severity
Original Paper | Climate sciences | 2025-06-03 20:00 EDT
Solomon H. Gebrechorkos, Justin Sheffield, Sergio M. Vicente-Serrano, Chris Funk, Diego G. Miralles, Jian Peng, Ellen Dyer, Joshua Talib, Hylke E. Beck, Michael B. Singer, Simon J. Dadson
Drought is one of the most common and complex natural hazards affecting the environment, economies and populations globally1,2,3,4. However, there are significant uncertainties in global drought trends4,5,6, and a limited understanding of the extent to which a key driver, atmospheric evaporative demand (AED), impacts the recent evolution of the magnitude, frequency, duration and areal extent of droughts. Here, by developing an ensemble of high-resolution global drought datasets for 1901-2022, we find an increasing trend in drought severity worldwide. Our findings suggest that AED has increased drought severity by an average of 40% globally. Not only are typically dry regions becoming drier but also wet areas are experiencing drying trends. During the past 5 years (2018-2022), the areas in drought have expanded by 74% on average compared with 1981-2017, with AED contributing to 58% of this increase. The year 2022 was record-breaking, with 30% of the global land area affected by moderate and extreme droughts, 42% of which was attributed to increased AED. Our findings indicate that AED has an increasingly important role in driving severe droughts and that this tendency will likely continue under future warming scenarios.
Climate sciences, Hydrology
CREM is a regulatory checkpoint of CAR and IL-15 signalling in NK cells
Original Paper | Cancer immunotherapy | 2025-06-03 20:00 EDT
Hind Rafei, Rafet Basar, Sunil Acharya, Yu-Sung Hsu, Pinghua Liu, Deqiang Zhang, Toszka Bohn, Qingnan Liang, Vakul Mohanty, Ranjan Upadhyay, Ping Li, Pravin Phadatare, Merve Dede, Donghai Xiong, Huihui Fan, Corry Mathew Jones, Sebastian Kunz, May Daher, Ana Karen Nunez Cortes, Mayra Shanley, Bin Liu, Sadie Mae Moseley, Chenyu Zhang, Dexing Fang, Pinaki Banerjee, Nadima Uprety, Ye Li, Rejeena Shrestha, Xinhai Wan, Hong Shen, Vernikka Woods, April Lamour Gilbert, Seema Rawal, Jinzhuang Dou, Yukun Tan, Jeong-Min Park, Francia Reyes Silva, Alexander Biederstädt, Mecit Kaplan, Xin Ru Jiang, Inci Biederstädt, Bijender Kumar, Silvia Tiberti, Madison Moore, Jingling Jin, Ryan Z. Yang, Luis Muniz-Feliciano, Samuel Rosemore, Paul Lin, Gary M. Deyter, Natalie Wall Fowlkes, Abhinav K. Jain, David Marin, Anirban Maitra, Ken Chen, Tobias Bopp, Elizabeth J. Shpall, Katayoun Rezvani
Chimeric antigen receptor (CAR) natural killer (NK) cell immunotherapy offers a promising approach against cancer1,2,3. However, the molecular mechanisms that regulate CAR-NK cell activity remain unclear. Here we identify the transcription factor cyclic AMP response element modulator (CREM) as a crucial regulator of NK cell function. Transcriptomic analysis revealed a significant induction of CREM in CAR-NK cells during the peak of effector function after adoptive transfer in a tumour mouse model, and this peak coincided with signatures of both activation and dysfunction. We demonstrate that both CAR activation and interleukin-15 signalling rapidly induce CREM upregulation in NK cells. Functionally, CREM deletion enhances CAR-NK cell effector function both in vitro and in vivo and increases resistance to tumour-induced immunosuppression after rechallenge. Mechanistically, we establish that induction of CREM is mediated by the PKA-CREB signalling pathway, which can be activated by immunoreceptor tyrosine-based activation motif signalling downstream of CAR activation or by interleukin-15. Finally, our findings reveal that CREM exerts its regulatory functions through epigenetic reprogramming of CAR-NK cells. Our results provide support for CREM as a therapeutic target to enhance the antitumour efficacy of CAR-NK cells.
Cancer immunotherapy, Innate immune cells, Interleukins, Translational immunology, Tumour immunology
Probing condensate microenvironments with a micropeptide killswitch
Original Paper | Cell biology | 2025-06-03 20:00 EDT
Yaotian Zhang, Ida Stöppelkamp, Pablo Fernandez-Pernas, Melanie Allram, Matthew Charman, Alexandre P. Magalhaes, Melanie Piedavent-Salomon, Gregor Sommer, Yu-Chieh Sung, Katrina Meyer, Nicholas Grams, Edwin Halko, Shivali Dongre, David Meierhofer, Michal Malszycki, Ibrahim A. Ilik, Tugce Aktas, Matthew L. Kraushar, Nadine Vastenhouw, Matthew D. Weitzman, Florian Grebien, Henri Niskanen, Denes Hnisz
Biomolecular condensates are thought to create subcellular microenvironments that have different physicochemical properties compared with their surrounding nucleoplasm or cytoplasm1,2,3,4,5. However, probing the microenvironments of condensates and their relationship to biological function is a major challenge because tools to selectively manipulate specific condensates in living cells are limited6,7,8,9. Here, we develop a non-natural micropeptide (that is, the killswitch) and a nanobody-based recruitment system as a universal approach to probe endogenous condensates, and demonstrate direct links between condensate microenvironments and function in cells. The killswitch is a hydrophobic, aromatic-rich sequence with the ability to self-associate, and has no homology to human proteins. When recruited to endogenous and disease-specific condensates in human cells, the killswitch immobilized condensate-forming proteins, leading to both predicted and unexpected effects. Targeting the killswitch to the nucleolar protein NPM1 altered nucleolar composition and reduced the mobility of a ribosomal protein in nucleoli. Targeting the killswitch to fusion oncoprotein condensates altered condensate compositions and inhibited the proliferation of condensate-driven leukaemia cells. In adenoviral nuclear condensates, the killswitch inhibited partitioning of capsid proteins into condensates and suppressed viral particle assembly. The results suggest that the microenvironment within cellular condensates has an essential contribution to non-stoichiometric enrichment and mobility of effector proteins. The killswitch is a widely applicable tool to alter the material properties of endogenous condensates and, as a consequence, to probe functions of condensates linked to diverse physiological and pathological processes.
Cell biology, Imaging, Mechanisms of disease, Nuclear organization
Loss of colonic fidelity enables multilineage plasticity and metastasis
Original Paper | Cancer genetics | 2025-06-03 20:00 EDT
Patrizia Cammareri, Michela Raponi, Yourae Hong, Caroline V. Billard, Nat Peckett, Yujia Zhu, Fausto D. Velez-Bravo, Nicholas T. Younger, Donnchadh S. Dunican, Sebastian Ö.-G. Pohl, Aslihan Bastem Akan, Nora J. Doleschall, John Falconer, Mark White, Jean Quinn, Kathryn Pennel, Roberta Garau, Sudhir B. Malla, Philip D. Dunne, Richard R. Meehan, Owen J. Sansom, Joanne Edwards, Malcolm G. Dunlop, Farhat V. N. Din, Sabine Tejpar, Colin W. Steele, Kevin B. Myant
Cancer cell plasticity enables the acquisition of new phenotypic features and is implicated as a major driver of metastatic progression1,2. Metastasis occurs mostly in the absence of additional genetic alterations3,4,5, which suggests that epigenetic mechanisms are important6. However, they remain poorly defined. Here we identify the chromatin-remodelling enzyme ATRX as a key regulator of colonic lineage fidelity and metastasis in colorectal cancer. Atrx loss promotes tumour invasion and metastasis, concomitant with a loss of colonic epithelial identity and the emergence of highly plastic mesenchymal and squamous-like cell states. Combined analysis of chromatin accessibility and enhancer mapping identified impairment of activity of the colonic lineage-specifying transcription factor HNF4A as a key mediator of these observed phenotypes. We identify squamous-like cells in human patient samples and a squamous-like expression signature that correlates with aggressive disease and poor patient prognosis. Collectively, our study defines the epigenetic maintenance of colonic epithelial identity by ATRX and HNF4A as suppressors of lineage plasticity and metastasis in colorectal cancer.
Cancer genetics, Cancer models, Colon cancer, Metastasis
A soft-clamped topological waveguide for phonons
Original Paper | Acoustics | 2025-06-03 20:00 EDT
Xiang Xi, Ilia Chernobrovkin, Jan Košata, Mads B. Kristensen, Eric Langman, Anders S. Sørensen, Oded Zilberberg, Albert Schliesser
Topological insulators were originally discovered for electron waves in condensed-matter systems. Recently, this concept has been transferred to bosonic systems such as photons1 and phonons2, which propagate in materials patterned with artificial lattices that emulate spin-Hall physics. This work has been motivated, in part, by the prospect of topologically protected transport along edge channels in on-chip circuits2,3. In principle, topology protects propagation against backscattering, but not against loss, which has remained limited to the dB cm-1 level for phononic waveguides, whether topological4,5,6,7 or not8,9,10,11,12,13,14,15,16,17,18,19. Here we combine advanced dissipation engineering20–in particular, the recently introduced method of soft clamping21–with the concept of valley-Hall topological insulators for phonons22,23,24,25,26. This enables on-chip phononic waveguides with propagation losses due to dissipation of 3 dB km-1 at room temperature, orders of magnitude below any previous chip-scale devices. The low losses also allow us to accurately quantify backscattering protection in topological phononic waveguides, using high-resolution ultrasound spectroscopy. We infer that phonons follow a sharp, 120° bend with a 99.99% probability instead of being scattered back, and less than one phonon in a million is lost. Our work will inspire new research directions on ultralow-loss phononic waveguides and will provide a clean bosonic system for investigating topological protection and non-Hermitian topological physics.
Acoustics, NEMS, Topological insulators
Multi-timescale reinforcement learning in the brain
Original Paper | Intelligence | 2025-06-03 20:00 EDT
Paul Masset, Pablo Tano, HyungGoo R. Kim, Athar N. Malik, Alexandre Pouget, Naoshige Uchida
To thrive in complex environments, animals and artificial agents must learn to act adaptively to maximize fitness and rewards. Such adaptive behaviour can be learned through reinforcement learning1, a class of algorithms that has been successful at training artificial agents2,3,4,5 and at characterizing the firing of dopaminergic neurons in the midbrain6,7,8. In classical reinforcement learning, agents discount future rewards exponentially according to a single timescale, known as the discount factor. Here we explore the presence of multiple timescales in biological reinforcement learning. We first show that reinforcement agents learning at a multitude of timescales possess distinct computational benefits. Next, we report that dopaminergic neurons in mice performing two behavioural tasks encode reward prediction error with a diversity of discount time constants. Our model explains the heterogeneity of temporal discounting in both cue-evoked transient responses and slower timescale fluctuations known as dopamine ramps. Crucially, the measured discount factor of individual neurons is correlated across the two tasks, suggesting that it is a cell-specific property. Together, our results provide a new paradigm for understanding functional heterogeneity in dopaminergic neurons and a mechanistic basis for the empirical observation that humans and animals use non-exponential discounts in many situations9,10,11,12, and open new avenues for the design of more-efficient reinforcement learning algorithms.
Intelligence, Learning algorithms, Reward
Increased CSF drainage by non-invasive manipulation of cervical lymphatics
Original Paper | Ageing | 2025-06-03 20:00 EDT
Hokyung Jin, Jin-Hui Yoon, Seon Pyo Hong, Yu Seok Hwang, Myung Jin Yang, Jieun Choi, Hae Jin Kang, Seung Eun Baek, Cheolhwa Jin, Junho Jung, Hae Jin Kim, Jincheol Seo, Jinyoung Won, Kyung Seob Lim, Chang-Yeop Jeon, Youngjeon Lee, Michael J. Davis, Hyung-Soon Park, Donald M. McDonald, Gou Young Koh
Cerebrospinal fluid (CSF) in the subarachnoid space around the brain drains to lymph nodes in the neck, but the connections and regulation have been challenging to identify1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24. Here we used fluorescent tracers in Prox1-GFP lymphatic reporter mice to map the pathway of CSF outflow through lymphatics to superficial cervical lymph nodes. CSF entered initial lymphatics in the meninges at the skull base and continued through extracranial periorbital, olfactory, nasopharyngeal and hard palate lymphatics, and then through smooth muscle-covered superficial cervical lymphatics to submandibular lymph nodes. Tracer studies in adult mice revealed that a substantial amount of total CSF outflow to the neck drained to superficial cervical lymph nodes. However, aged mice had fewer lymphatics in the nasal mucosa and hard palate and reduced CSF outflow to cervical lymph nodes. Superficial cervical lymphatics in aged mice had increased endothelial cell expression of Nos3, encoding endothelial nitric oxide synthase (eNOS), but had less eNOS protein and impaired nitric oxide signalling. Manipulation of superficial cervical lymphatics through intact skin by a force-regulated mechanical device doubled CSF outflow and corrected drainage impairment in aged mice. This manipulation increased CSF outflow by compressing superficial cervical lymphatics while having little effect on their normal spontaneous contractions. Overall, the findings highlight the importance of superficial cervical lymphatics for CSF outflow and the potential for reversing CSF drainage impairment by non-invasive mechanical stimulation.
Ageing, Cardiovascular biology
Drivers of the extreme North Atlantic marine heatwave during 2023
Original Paper | Attribution | 2025-06-03 20:00 EDT
Matthew H. England, Zhi Li, Maurice F. Huguenin, Andrew E. Kiss, Alex Sen Gupta, Ryan M. Holmes, Stefan Rahmstorf
North Atlantic Ocean circulation and temperature patterns profoundly influence global and regional climate across all timescales, from synoptic1 to seasonal2,3,4, decadal5, multidecadal6,7 and beyond8,9. During 2023, an extreme and near-basin-scale marine heatwave developed during Northern Hemisphere summer, peaking in July. The warming spread across virtually all regions of the North Atlantic, including the subpolar ocean, where a cooling trend over the past 50-100 years has been linked to a slowdown in the meridional overturning circulation10,11. Yet the mechanisms that led to this exceptional surface ocean warming remain unclear. Here we use observationally constrained atmospheric reanalyses alongside ocean observations and model simulations to show that air-sea heat fluxes acting on an extremely shallow surface mixed layer, rather than anomalous ocean heat transport, were responsible for this extreme ocean warming event. The dominant driver is shown to be anomalously weak winds leading to strongly shoaling (shallowing) mixed layers, resulting in a rapid temperature increase in a shallow surface layer of the North Atlantic. Furthermore, solar radiation anomalies made regional-scale warming contributions in locations that approximately correspond to some of the region’s main shipping lanes, suggesting that reduced sulfate emissions could also have played a localized role. With a trend towards shallower mixed layers observed over recent decades, and projections that this will continue into the future, the severity of North Atlantic marine heatwaves is set to worsen.
Attribution, Physical oceanography
Concurrent loss of the Y chromosome in cancer and T cells impacts outcome
Original Paper | Cancer microenvironment | 2025-06-03 20:00 EDT
Xingyu Chen, Yiling Shen, Suhyeon Choi, Hany A. Abdel-Hafiz, Mukta Basu, Lena Hoelzen, Martina Tufano, Saravana Kumar Kailasam Mani, Maryam Ranjpour, Jiani Zhu, V. Krishnan Ramanujan, Ekaterina K. Koltsova, Vinicius F. Calsavara, Simon R. V. Knott, Dan Theodorescu
Loss of the Y chromosome (LOY) in peripheral blood mononuclear cells (PBMCs) is the most common somatic alteration in men and is associated with higher mortality from epithelial cancers1,2,3. In tumours, epithelial LOY is also associated with poor survival4,5,6,7. This raises several fundamental questions, such as why LOY in PBMCs drives cancer mortality and whether there is a relationship between LOY in PBMCs, PBMC-derived immune cells and cancer cells (and, if so, what its consequences are). We sought to answer these questions through a comprehensive pan-cancer analysis of bulk and single-cell RNA sequencing data from 29 human tumour types, along with autochthonous and syngeneic mouse models. In human and mouse tumours, malignant epithelial cells had the highest LOY prevalence, yet LOY was also present in tumour stromal and immune cells, with LOY in malignant epithelial cells predicting LOY in benign cells. LOY also correlated between paired tumour and PBMC samples from patients. Among benign cells, LOY induced the strongest shift in CD4+ and CD8+ T cells, with both showing transcriptomic signatures of immunosuppression. Furthermore, the magnitude of LOY in epithelial cells, CD4+ T cells and CD8+ T cells independently predicts survival, with tumours exhibiting concurrent epithelial and T cell LOY having the worst outcomes. Here we establish a model that links LOY in immune cells to LOY in malignant cells, which may explain in part why LOY in PBMCs is associated with increased cancer mortality.
Cancer microenvironment, Chromosomes, Prognostic markers
Ischaemic endothelial necroptosis induces haemolysis and COVID-19 angiopathy
Original Paper | Cell signalling | 2025-06-03 20:00 EDT
Mike C. L. Wu, Ethan Italiano, Rocko Jarvis-Child, Imala Alwis, Rhyll Smythe, Eduardo A. Albornoz, Jonathan Noonan, Marie Portelli, Marissa Baptista, Jessica Maclean, Pashtana Noori, Jinglu Yang, John D. Lee, James D. McFadyen, Alexandra F. Sharland, Trent M. Woodruff, Andre L. Samson, Amy Rapkiewicz, Tessa J. Barrett, Alan Pham, Simone M. Schoenwaelder, Yuping Yuan, Shaun P. Jackson
Microangiopathy is a major complication of SARS-CoV-2 infection and contributes to the acute and chronic complications of the disease1. Endotheliopathy and dysregulated blood coagulation are prominent in COVID-19 and are considered to be major causes of microvascular obstruction1,2. Here we demonstrate extensive endothelial cell (EC) death in the microvasculature of COVID-19 organs. Notably, EC death was not associated with fibrin formation or platelet deposition, but was linked to microvascular red blood cell (RBC) haemolysis. Importantly, this RBC microangiopathy was associated with ischaemia-reperfusion injury, and was prominent in the microvasculature of humans with myocardial infarction, gut ischaemia, stroke, and septic and cardiogenic shock. Mechanistically, ischaemia induced MLKL-dependent EC necroptosis and complement-dependent RBC haemolysis. Deposition of haemolysed RBC membranes at sites of EC death resulted in the development of a previously unrecognized haemostatic mechanism preventing microvascular bleeding. Exaggeration of this haemolytic response promoted RBC aggregation and microvascular obstruction. Genetic deletion of Mlkl from ECs decreased RBC haemolysis, microvascular obstruction and reduced ischaemic organ injury. Our studies demonstrate the existence of a RBC haemostatic mechanism induced by dying ECs, functioning independently of platelets and fibrin. Therapeutic targeting of this haemolytic process may reduce microvascular obstruction in COVID-19, and other major human diseases associated with organ ischaemia.
Cell signalling, Cellular imaging, Experimental models of disease, Mechanisms of disease
Acetolysis for epoxy-amine carbon fibre-reinforced polymer recycling
Original Paper | Chemical engineering | 2025-06-03 20:00 EDT
Ciaran W. Lahive, Stephen H. Dempsey, Sydney E. Reiber, Ajinkya Pal, Katherine R. Stevenson, William E. Michener, Hannah M. Alt, Kelsey J. Ramirez, Erik G. Rognerud, Clarissa L. Lincoln, Ryan W. Clarke, Jason S. DesVeaux, Taylor Uekert, Nicholas A. Rorrer, Katrina M. Knauer, Gregg T. Beckham
Carbon fibre-reinforced polymers (CFRPs) are used in many applications in the global energy transition, including for lightweighting aircraft and vehicles and in wind turbine blades, shipping containers and gas storage vessels1,2,3,4. Given the high cost and energy-intensive manufacture of CFRPs5,6,7, recycling strategies are needed that recover intact carbon fibres and the epoxy-amine resin components. Here we show that acetic acid efficiently depolymerizes both aliphatic and aromatic epoxy-amine thermosets used in CFRPs to recoverable monomers, yielding pristine carbon fibres. Deconstruction of materials from multiple sectors demonstrates the broad applicability of this approach, providing clean fibres from 2 h reactions. The optimal conditions were scaled to 80.0 g of post-consumer CFRPs, and demonstrative composites were fabricated from the recycled carbon fibres, which were recycled two more times, maintaining their strength throughout. Process modelling and techno-economic analysis, with feedstock cost informed by wind turbine blade waste generation8, indicates this method is cost effective, with a minimum selling price of US$1.50 per kg for recycled carbon fibres whereas life cycle assessment shows process greenhouse gas emissions around 99% lower than virgin carbon fibre production. Overall, this approach could enable recycling of industrial CFRPs as it provides clean, mechanically viable recycled carbon fibres and recoverable resin monomers from the thermoset.
Chemical engineering, Polymer chemistry, Sustainability
Structural insights into human Pol III transcription initiation in action
Original Paper | Cryoelectron microscopy | 2025-06-03 20:00 EDT
Qianmin Wang, Yulei Ren, Qianwei Jin, Xizi Chen, Yanhui Xu
RNA polymerase III (Pol III) transcribes highly demanded RNAs grouped into three types of classical promoters, including type 1 (5S rRNA), type 2 (tRNA) and type 3 (short non-coding RNAs, such as U6, 7SK and RNase H1) promoters1,2,3,4,5,6,7. While structures of the Pol III preinitiation complex (PIC)8,9,10,11 and elongation complex (EC)12,13,14,15,16 have been determined, the mechanism underlying the transition from initiation to elongation remains unclear. Here we reconstituted seven human Pol III transcribing complexes (TC4, TC5, TC6, TC8, TC10, TC12 and TC13) halted on U6 promoters with nascent RNAs of 4-13 nucleotides. Cryo-electron microscopy structures captured initially transcribing complexes (ITCs; TC4 and TC5) and ECs (TC6-13). Together with KMnO4 footprinting, the data reveal extensive modular rearrangements: the transcription bubble expands from PIC to TC5, followed by general transcription factor (GTF) dissociation and abrupt bubble collapse from TC5 to TC6, marking the ITC-EC transition. In TC5, SNAPc and TFIIIB remain bound to the promoter and Pol III, while the RNA-DNA hybrid adopts a tilted conformation with template DNA blocked by BRF2, a TFIIIB subunit. Hybrid forward translocation during ITC-EC transition triggers BRF2-finger retraction, GTF release and transcription-bubble collapse. Pol III then escapes the promoter while GTFs stay bound upstream, potentially enabling reinitiation. These findings reveal molecular insights into Pol III dynamics and reinitiation mechanisms on type 3 promoters of highly demanded small RNAs, with the earliest documented initiation-elongation transition for an RNA polymerase.
Cryoelectron microscopy, Transcription
Subnucleosome preference of human chromatin remodeller SMARCAD1
Original Paper | Chromatin remodelling | 2025-06-03 20:00 EDT
Pengjing Hu, Jingxi Sun, Hongyao Sun, Kangjing Chen, Youyang Sia, Xian Xia, Qiaoran Xi, Zhucheng Chen
Chromatin remodellers are pivotal in the regulation of nucleosome dynamics in cells, and they are important for chromatin packaging, transcription, replication and DNA repair1. Here we show that the human chromatin remodeller SMARCAD1 exhibits a substrate preference for subnucleosomal particles over the canonical nucleosome. Cryo-electron microscopy structures of SMARCAD1 bound to the nucleosome and hexasome provide mechanistic insights into the substrate selectivity. SMARCAD1 binds to the hexasome through multiple family-specific elements that are essential for the functions in vitro and in cells. The enzyme binds to the canonical nucleosome in an inactive conformation, which accounts for its diminished activity towards the nucleosome. Notably, the histone chaperone FACT complex acts synergistically with H2A-H2B to promote the activity of SMARCAD1 in nucleosome remodelling. Together, our findings reveal an avenue for chromatin regulation, whereby subnucleosomes are remodelled through an ATP-dependent process.
Chromatin remodelling, Cryoelectron microscopy
Nature Nanotechnology
Unidirectional guided resonance continuum of Dirac bands in WS2 bilayer metasurfaces
Original Paper | Nanophotonics and plasmonics | 2025-06-03 20:00 EDT
Daegwang Choi, Ki Young Lee, Dong-Jin Shin, Jae Woong Yoon, Su-Hyun Gong
Unidirectional guided resonances are crucial for enhancing the efficiency and performance of various photonic devices, such as couplers and antennas. However, unidirectional guided resonances have been reported only under discrete frequency-wavevector points on a dispersion band, which require accidental interference configurations. Here we show that unidirectional guided resonances can continuously exist across nearly the entire band structure in glide-symmetric bilayer metasurfaces. This continuous excitation of unidirectional guided resonances originates from a synergistic effect between anomalous orthogonality and vertically asymmetric geometry, which is achieved by a Dirac crossing band that preserves glide symmetry. We realize the glide-symmetric bilayer metasurfaces by stacking two WS2 metasurface layers. Angle-resolved emission spectra directly reveal this unidirectional guided resonance continuum. Our work suggests a fundamental solution to existing narrow-band constraints on unidirectional emission and absorption.
Nanophotonics and plasmonics, Two-dimensional materials
Nature Physics
High-efficiency optical training of itinerant two-dimensional magnets
Original Paper | Ferromagnetism | 2025-06-03 20:00 EDT
Ti Xie, Jierui Liang, Dhritiman Bhattacharya, Hasitha Suriya Arachchige, Victor M. Yakovenko, David G. Mandrus, Zi Qiang Qiu, Kai Liu, Cheng Gong
Cooling a material into a ferromagnetic phase can produce arbitrary metastable patterns of magnetic domains rather than a spatially uniform magnetic state. Control over the formation of these patterns could provide non-chemical methods of creating spintronic devices. Here we demonstrate high-efficiency optical training of magnetic domain formation in the two-dimensional van der Waals magnet Fe3GeTe2 during zero-field cooling. At ultralow power densities of around 20 µW µm-2, electrons excited by linearly polarized photons catalyse the formation of larger domains for both spin orientations. Furthermore, circularly polarized photons of the same low power density produce a single domain with its magnetization orientation determined by the optical helicity. We propose that the emergence of this single domain is caused by the optically injected spin-polarized electrons acting as initial magnetic seeds that guide different regions of the sample into the same spin orientation. Our work presents an unconventional route to tailoring spin textures in two-dimensional materials.
Ferromagnetism, Two-dimensional materials
Physical Review Letters
Extended $\delta N$ Formalism: Nonspatially Flat Separate-Universe Approach
Research article | Cosmology | 2025-06-03 06:00 EDT
Danilo Artigas, Shi Pi, and Takahiro Tanaka
The $\delta N$ formalism is a powerful approach to compute nonlinearly the large-scale evolution of the comoving curvature perturbation $\zeta $. It assumes a set of FLRW patches that evolve independently, but in doing so, all the gradient terms are discarded, which are not negligibly small in models beyond slow roll. In this Letter, we extend the formalism to capture these gradient corrections by encoding them in a homogeneous-spatial-curvature contribution assigned to each FLRW patch. For a concrete example, we apply this formalism to the ultra-slow-roll inflation, and find that it can correctly describe the large-scale evolution of the comoving curvature perturbation from the horizon exit. We also briefly discuss non-Gaussianities in this context.
Phys. Rev. Lett. 134, 221001 (2025)
Cosmology, Inflation
Black Hole Supercolliders
Research article | General relativity | 2025-06-03 06:00 EDT
Andrew Mummery and Joseph Silk
We show that collisions between particles free falling from infinity and a disk of material plunging off the retrograde innermost stable circular orbit of a near-extremal Kerr black hole is the unique astronomically natural way in which to create a gravitational particle accelerator with center of mass energies at the tens to hundreds of teraelectronvolt range; in other words, a supercollider.
Phys. Rev. Lett. 134, 221401 (2025)
General relativity, Particle astrophysics, Accretion disk & black-hole plasma, Astronomical black holes
Stochastic Dynamics of Incoherent Branched Flows
Research article | Light propagation in random media | 2025-06-03 06:00 EDT
Josselin Garnier, Antonio Picozzi, and Theo Torres
A stochastic formulation demonstrates that interference effects significantly modify the statistical properties of branched flows.
Phys. Rev. Lett. 134, 223803 (2025)
Light propagation in random media, Wave scattering, Disordered systems, Stochastic analysis
Transient Fluted Films behind Falling Water Columns
Research article | Capillary waves | 2025-06-03 06:00 EDT
Abhijit K. Kushwaha, Matthew B. Jones, Jesse Belden, Nathan Speirs, and Tadd T. Truscott
When a column of water drains from a vertical tube, it often leaves behind a trailing film that forms intricate, axisymmetric liquid structures. Using high-speed imaging and first-principles modeling, we investigate the formation and breakup of these fluted films and demonstrate that their diverse morphologies arise from the evolving balance of inertia, surface tension, gravity, and viscous forces. By analyzing the characteristic timescales for film emergence, retraction, and rupture, we classify the observed behaviors into distinct regimes and predict the transitions between them. Our theoretical framework captures the transient velocity and thickness of the film at the tube exit and yields regime boundaries that closely match experimental observations. These results not only explain a deceptively simple fluid dynamic system but also provide insight into film stability, merging, and rupture processes relevant to falling film evaporators, coating flows, and capillary-inertial instabilities across soft matter and multiphase systems.
Phys. Rev. Lett. 134, 224001 (2025)
Capillary waves, Growth, Instability of free-surface flows, Shear waves, Surface tension effects, Thin fluid films, Wakes & jets, Water
Anomalous Doppler Effect in Superfluid and Supersolid Atomic Gases
Research article | Dipolar gases | 2025-06-03 06:00 EDT
Tomasz Zawiślak, Marija Šindik, Sandro Stringari, and Alessio Recati
By employing the formalism of hydrodynamics, we derive novel analytic predictions for the Doppler effect in superfluids with broken Galilean invariance and hosting persistent currents at zero temperature. We consider two scenarios: when Galilean invariance is broken explicitly (by external potentials) and spontaneously, as it happens in a supersolid. In the former case, the presence of a stationary current affects the propagation of sound via an anomalous Doppler term proportional to the density derivative of the superfluid fraction. In supersolids, where, according to Goldstone theorem, distinct sounds of hybrid superfluid and crystal nature can propagate, the Doppler effect can be very different for each sound. Quantitative estimates of the Doppler shifts are obtained for Bose-Einstein condensed atomic gases, described by Gross-Pitaevskii theory. The estimates are obtained both calculating the thermodynamic parameters entering the hydrodynamic results and from full time-dependent simulations.
Phys. Rev. Lett. 134, 226001 (2025)
Dipolar gases, Phonons, Atomic gases, Bose-Einstein condensates, Superfluids, Supersolids, Ultracold gases, Hydrodynamic models, Numerical techniques, Two-fluid & multi-fluid model
Coupled Electron-Phonon Hydrodynamics in Two-Dimensional Semiconductors
Research article | Electron-phonon coupling | 2025-06-03 06:00 EDT
Yujie Quan and Bolin Liao
Electronic and thermal transport properties in two-dimensional (2D) semiconductors have been extensively investigated due to their potential to miniaturize transistors. Microscopically, electron-phonon interactions are considered the dominant momentum relaxation mechanism for electrons that limits carrier mobility beyond cryogenic temperatures. However, when electrons and phonons are considered as a single system, electron-phonon interactions conserve the total momentum and energy, leading to the possibility of low-dissipation transport. In this Letter, we systematically investigate the momentum circulation, in which momentum previously transferred from electrons to phonons (or vice versa) can be pumped back to the original carriers through interactions between nonequilibrium electrons and phonons, and its impact on carrier transport properties in 2D semiconductors with strong electron-phonon interactions. We find that, when strong momentum circulation is taken into account, the total momentum in the coupled electron-phonon system is weakly dissipated, leading to a coupled electron-phonon hydrodynamic transport regime, in which electrons and phonons exhibit a joint drift motion rather than separate diffusive behaviors. In this transport regime, charge transport properties are significantly enhanced. Contrary to previous belief, our results demonstrate that low-dissipation charge transport can occur despite strong electron-phonon interactions when there is effective momentum circulation between electrons and phonons. Our Letter advances fundamental understandings of carrier transport in 2D semiconductors.
Phys. Rev. Lett. 134, 226301 (2025)
Electron-phonon coupling, Phonons, Transport phenomena, 2-dimensional systems, Semiconductors, First-principles calculations
Origin of the Hidden Energy Scale and the $f$ Ratio in Geometrically Frustrated Magnets
Research article | Frustrated magnetism | 2025-06-03 06:00 EDT
Phillip Popp, Arthur P. Ramirez, and Sergey Syzranov
Sufficiently clean geometrically frustrated (GF) magnets are the largest class of candidate materials that may host quantum spin liquids (QSLs). Some of them have been shown to exhibit spin-glass freezing, potentially precluding QSLs, at the ‘’hidden energy scale,’’ which is significantly lower than the microscopic energy scale of spin interactions. Here, we investigate the origin of the hidden energy scale and its relationship to the $f$ ratio, the figure of merit for the degree of frustration in GF magnetic materials. The available experimental and numerical data provide evidence that GF magnets display, universally, two distinct temperature scales in the specific heat, the lowest of which is of the order of the hidden energy scale ${T}^{\ast}$. We argue that this scale is determined by nonmagnetic excitations, similar to spin exchanges in chains of spins. The collective entropy of such excitations matches the entropy of the ground states of the Ising model on the same lattice, which provides a way to verify the proposed scenario in experiment. We demonstrate that in the presence of quenched disorder, a broad class of materials exhibits spin-glass freezing at temperatures of order ${T}^{\ast}$, in accordance with experimental observations. As ${T}^{\ast}$ is a property of the clean GF medium, it leads to a constraint on the $f$ ratio.
Phys. Rev. Lett. 134, 226701 (2025)
Frustrated magnetism, Magnetic order, Magnetic phase transitions, Quantum spin liquid, Magnetic insulators, Heisenberg model, Ising model
Experimental Realization of an Analog of Entanglement between Two Brownian Particles
Research article | Brownian motion | 2025-06-03 06:00 EDT
Theerthagiri L. and S. Ciliberto
We experimentally investigate the statistical properties of a classical analog of quantum entanglement between two Brownian particles connected by an elastic force and maintained at different temperatures through separate heat reservoirs. Uncertainty relations between coordinates and coarse-grained velocity can produce a phenomenon similar to quantum entanglement, where temperature plays the role of Planck’s constant. The theoretical analysis matches the experimental results, confirming that the interconnected particles exhibit Brownian quantum-inspired classical correlation entanglement. This effect arises from a coarse-grained description of Brownian motion and vanishes at a finer resolution. The coarsening scale range is measured too.
Phys. Rev. Lett. 134, 227101 (2025)
Brownian motion, Fluctuations & noise, Quantum correlations, foundations & formalism
Physical Review X
Emergent Holographic Forces from Tensor Networks and Criticality
Research article | Coherent control | 2025-06-03 06:00 EDT
Rahul Sahay, Mikhail D. Lukin, and Jordan Cotler
A simplified quantum gravity model, which can be simulated using current quantum technologies, replicates key features of Einstein’s gravity, offering insights into the quantum nature of spacetime and paving the way for experimental exploration.
Phys. Rev. X 15, 021078 (2025)
Coherent control, Gravitation, Gravity in dimensions other than four, Quantum computation, Quantum field theory (low energy), Quantum gravity, Quantum information processing, Quantum information theory, Quantum simulation, Rydberg gases, Quantum spin chains
Fast, Robust, and Laser-Free Universal Entangling Gates for Trapped-Ion Quantum Computing
Research article | Quantum computation | 2025-06-03 06:00 EDT
Markus Nünnerich, Daniel Cohen, Patrick Barthel, Patrick H. Huber, Dorna Niroomand, Alex Retzker, and Christof Wunderlich
A new radio-frequency-driven gate is an order of magnitude faster than previous ones in static magnetic gradients and has a simplified design suitable for large-scale applications in different quantum computing platforms.
Phys. Rev. X 15, 021079 (2025)
Quantum computation, Quantum gates, Quantum information architectures & platforms, Trapped ions
Review of Modern Physics
Colloquium: Qudits for decomposing multiqubit gates and realizing quantum algorithms
Research article | Quantum algorithms & computation | 2025-06-03 06:00 EDT
Evgeniy O. Kiktenko, Anastasiia S. Nikolaeva, and Aleksey K. Fedorov
Two-level systems–bits or qubits–are understood to generally be the most efficient primitives for information processing, classical or quantum. But this is not to say that there are no roles to be played by multilevel systems. This Colloquium surveys these possible roles for the quantum case. Here we speak of qudits: d-level quantum systems. In one interesting example, the use of just one three-level system permits a drastic simplification of the “Toffoli gate,” the basic three-qubit primitive of reversible logic. A survey is given of various qudit-qubit embeddings, and the current state of quantum computing experiments using qudits is reviewed.
Rev. Mod. Phys. 97, 021003 (2025)
Quantum algorithms & computation, Quantum circuits, Quantum gates, Qudits, Atoms, Trapped ions
arXiv
Nonlinear Dielectric Decrement of Electrolyte Solutions: an Effective Medium Approach
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Hypothesis. The dielectric constant of an electrolyte solution, which determines electrostatic interactions between colloids and interfaces, depends nonlinearly on the salinity and also on the type of salt. The linear decrement at dilute solutions is due to the reduced polarizability in the hydration shell around an ion. However, the full hydration volume cannot explain the experimental solubility, which indicates the hydration volume should decrease at high salinity. Volume reduction of the hydration shell is supposed to weaken dielectric decrement and thus should be relevant to the nonlinear decrement. Simulations. According to the effective medium theory for the permittivity of heterogeneous media, we derive an equation which relates the dielectric constant with the dielectric cavities created by the hydrated cations and anions, and the effect of partial dehydration at high salinity is taken into account. Findings. Analysis of experiments on monovalent electrolytes suggests that weakened dielectric decrement at high salinity originates primarily from the partial dehydration. Furthermore, the onset volume fraction of the partial dehydration is found to be salt-specific, and is correlated with the solvation free energy. Our results suggest that while the reduced polarizability of the hydration shell determines the linear dielectric decrement at low salinity, ion-specific tendency of dehydration is responsible for nonlinear dielectric decrement at high salinity.
Soft Condensed Matter (cond-mat.soft)
Journal of Colloid and Interface Science, 2023, 646: 354-360
Re-experiment Smart: a Novel Method to Enhance Data-driven Prediction of Mechanical Properties of Epoxy Polymers
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Wanshan Cui, Yejin Jeong, Inwook Song, Gyuri Kim, Minsang Kwon, Donghun Lee
Accurate prediction of polymer material properties through data-driven approaches greatly accelerates novel material development by reducing redundant experiments and trial-and-error processes. However, inevitable outliers in empirical measurements can severely skew machine learning results, leading to erroneous prediction models and suboptimal material designs. To address this limitation, we propose a novel approach to enhance dataset quality efficiently by integrating multi-algorithm outlier detection with selective re-experimentation of unreliable outlier cases. To validate the empirical effectiveness of the approach, we systematically construct a new dataset containing 701 measurements of three key mechanical properties: glass transition temperature ($ T_g$ ), tan $ \delta$ peak, and crosslinking density ($ v_{c}$ ). To demonstrate its general applicability, we report the performance improvements across multiple machine learning models, including Elastic Net, SVR, Random Forest, and TPOT, to predict the three key properties. Our method reliably reduces prediction error (RMSE) and significantly improves accuracy with minimal additional experimental work, requiring only about 5% of the dataset to be this http URL findings highlight the importance of data quality enhancement in achieving reliable machine learning applications in polymer science and present a scalable strategy for improving predictive reliability in materials science.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI)
27 pages, 8 figures
Anyon superconductivity and plateau transitions in doped fractional quantum anomalous Hall insulators
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Pavel A. Nosov, Zhaoyu Han, Eslam Khalaf
Recent experiments reported evidence of superconductivity and re-entrant integer quantum anomalous Hall (RIQAH) insulator upon doping the $ \nu_e = 2/3$ fractional quantum anomalous Hall states (FQAH) in twisted MoTe$ {}_2$ , separated by narrow resistive regions. Anyons of a FQAH generally have a finite effective mass, and when described by anyon-flux composite fermions (CF), experience statistical magnetic fields with a commensurate filling. Here, we show that most of the experimental observations can be explained by invoking the effects of disorder on the Landau-Hofstadter bands of CFs. In particular, by making minimal assumptions about the anyon energetics and dispersion, we show that doping anyons drives plateau transitions of CFs into integer quantum Hall states, which physically corresponds to either to a superconductor or to a RIQAH phase. We develop a dictionary that allows us to infer the response in these phases and the critical regions from the knowledge of the response functions of the plateau transitions. In particular, this allows us to relate the superfluid stiffness of the superconductor to the polarizability of CFs. As a first step towards a quantitative understanding, we borrow results from the celebrated integer quantum Hall plateau transitions to make quantitative prediction for the critical behavior of the superfluid stiffness, longitudinal and Hall conductivity, and response to out-of-plane magnetic field, all of which agree reasonably well with the experimental observations. Our results provide strong support for anyon superconductivity being the mechanism for the observed superconductor in the vicinity of the $ \nu_e = 2/3$ FQAH insulator.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
6 pages, 3 figures
Classical spin liquids from frustrated Ising models in hyperbolic space
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Fabian Köhler, Johanna Erdmenger, Roderich Moessner, Matthias Vojta
Antiferromagnetic Ising models on frustrated lattices can realize classical spin liquids, with highly degenerate ground states and, possibly, fractionalized excitations and emergent gauge fields. Motivated by the recent interest in many-body system in negatively curved space, we study hyperbolic frustrated Ising models. Specifically, we consider nearest-neighbor Ising models on tesselations with odd-length loops in two-dimensional hyperbolic space. For finite systems with open boundaries we determine the ground-state degeneracy exactly, and we perform extensive finite-temperature Monte-Carlo simulations to obtain thermodynamic data as well as correlation functions. We show that the shape of the boundary, constituting an extensive part of the system, can be used to control low-energy states: Depending on the boundary, we find ordered or disordered ground states. Our results demonstrate how geometric frustration acts in curved space to produce classical spin liquids.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Anyon delocalization transitions out of a disordered FQAH insulator
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Zhengyan Darius Shi, T. Senthil
Motivated by the experimental discovery of the fractional quantum anomalous Hall (FQAH) effect, we develop a theory of doping-induced transitions out of the $ \nu = 2/3$ lattice Jain state in the presence of quenched disorder. We show that disorder strongly affects the evolution into the conducting phases described in our previous work. The delocalization of charge $ 2/3$ anyons leads to a chiral topological superconductor through a direct second order transition for a smooth random potential with long wavelength modulations. The longitudinal resistance has a universal peak at the associated quantum critical point. For short wavelength disorder, this transition generically splits into three distinct ones with intermediate insulating topological phases. If instead, the charge $ 1/3$ anyon delocalizes, then at low doping the result is a Reentrant Integer Quantum Hall state with $ \rho_{xy} = h/e^2$ . At higher doping this undergoes a second transition to a Fermi liquid metal. We show that this framework provides a plausible explanation for the complex phase diagram recently observed in twisted MoTe$ _2$ near $ \nu = 2/3$ and discuss future experiments that can test our theory in more detail.
Strongly Correlated Electrons (cond-mat.str-el)
12 pages, 6 figures
Line shapes in time- and angle-resolved photoemission spectroscopy explored by machine learning
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Tami C. Meyer, Gesa-R. Siemann, Paulina Majchrzak, Thomas Seyller, Jennifer Rigden, Yu Zhang, Emma Springate, Charlotte Sanders, Philip Hofmann
Time- and angle-resolved photoemission spectroscopy is a powerful technique for investigating the dynamics of excited carriers in quantum materials. Typically, data analysis proceeds via the inspection of time distribution curves (TDCs), which represent the time-dependent photoemission intensity in a region of interest – often chosen somewhat arbitrarily – in energy-momentum space. Here, we employ $ k$ -means, an unsupervised machine learning technique, to systematically investigate trends in TDC line shape for quasi-free-standing monolayer graphene and for a simple analytical model. Our analysis reveals how finite energy and time resolution can affect the TDC line shape. We discuss how this can be taken into account in a quantitative analysis, and under what conditions the time-dependent photoemission intensity after laser excitation can be approximated by a simple exponential decay.
Strongly Correlated Electrons (cond-mat.str-el)
Microscopic mechanisms of Strong Electron Scattering and Giant Anomalous Hall Effect in high-Curie-temperature Fe3GaTe2 van der Waals Films
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Zhengxiao Li, Xin Lin, Yu Zou, Fanjie Tan, Wenliang Zhu, Lijun Zhu
Van der Waals ferromagnet Fe3GaTe2 with room-temperature perpendicular magnetic anisotropy and strong anomalous Hall effect has attracted considerable interest for their potential in spintronics. However, the microscopic mechanisms and manipulation of the electron scattering and the anomalous Hall effect of Fe3GaTe2 have remained unsettled. Here, we demonstrate strong tuning of the electron scattering and anomalous Hall effect of pattern-defined Fe3GaTe2 Hall-bar devices with perpendicular magnetic anisotropy, high Curie temperature (340 K, as high as that of Fe3GaTe2 bulk), and giant anomalous Hall effect by varying the layer thickness and temperature. Temperature-dependent resistivity experiments reveal that the electron scattering of the high-quality Fe3GaTe2 is dominated by impurity scattering and phonon scattering, regardless of the thickness. Combined temperature- and thickness-dependent scaling analyses of the anomalous Hall resistivity reveal that the anomalous Hall effect of the Fe3GaTe2 is predominantly from the positive, temperature-independent skew-scattering contribution that competes with negative temperature-independent, side-jump contribution, and negative, temperature-dependent intrinsic Berry-curvature contribution. The intrinsic anomalous Hall conductivity decreases rapidly with increasing impurity scattering, which is consistent with the characteristic variation of intrinsic Hall conductivities in the dirty-metal regime. These findings advance the understanding of electron scattering and the anomalous Hall effect in van der Waals magnets and would benefit the application of the Fe3GaTe2 in spintronics.
Materials Science (cond-mat.mtrl-sci)
Tunable magnons in a dual-gated 2D antiferromagnet
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Nele Stetzuhn, Abhijeet M. Kumar, Sviatoslav Kovalchuk, Denis Yagodkin, Louis Simon, Samuel Mañas-Valero, Eugenio Coronado, Takashi Taniguchi, Kenji Watanabe, Deepika Gill, Sangeeta Sharma, Piet Brouwer, Clemens von Korff Schmising, Stefan Eisebitt, Kirill I. Bolotin
The layered antiferromagnet CrSBr features magnons coupled to other quasiparticles, including excitons and polaritons, enabling their easy optical accessibility. In this work, we investigate the tunability of magnons in few-layered devices in response to changes in carrier density and the application of a perpendicular electric field. We demonstrate an on-chip tunability of the in- and out-of-phase magnon frequencies by up to 2 GHz. While the frequencies of both modes increase with the electron density, we observe an asymmetric response with respect to the electric field in a dual-gated trilayer device. To understand the mechanism of this disparity, we develop a layer-resolved macrospin model describing the magnetic dynamics in thin, non-uniformly doped devices. Through this model we establish the doping- and electric-field-dependence of the exchange interaction, magnetic anisotropy, and magnetic moment of individual layers. Our results advance the applications of gate-tunable magnonic devices based on 2D materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Impact of the honeycomb spin-lattice on topological magnons and edge states in ferromagnetic 2D skyrmion crystals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Doried Ghader, Bilal Jabakhanji
We theoretically investigate the magnon band topology and associated topological edge states (TESs) in Neel-type ferromagnetic skyrmion crystals (SkXs) stabilized on a two-dimensional honeycomb lattice, using parameters relevant to monolayer CrI3. Employing stochastic Landau-Lifshitz-Gilbert simulations and discrete Holstein-Primakoff bosonization, we analyze the impact of the honeycomb spin-lattice structure on the magnonic spectrum, in contrast to the extensively studied triangular spin-lattice SkXs. Our analysis identifies topological features unique to the honeycomb lattice. In particular, certain characteristic magnon modes (e.g., elliptical distortion and triangular distortion modes) acquire nontrivial Chern numbers absent in triangular-based SkXs. Moreover, contrary to predictions based on triangular spin-lattice SkXs, we find that the counterclockwise (CCW)-breathing magnonic gap exhibits topological behavior only at large Dzyaloshinskii-Moriya interactions (DMI), losing its universality with decreasing DMI strength. Meanwhile, the second magnon gap consistently hosts robust TESs across the entire range of DMI and magnetic fields studied, closing at critical fields through field-induced topological phase transitions. The study further uncovers a remarkable richness in the magnon topology, identifying 65 distinct topological magnon phases generated by magnetic-field-driven skyrmion deformation. These findings underscore the profound role of lattice geometry in shaping magnon topology in non-collinear spin textures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
Supplementary material will be available with the published version
Static vs dynamic rough energy landscapes: Where is diffusion faster?
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-04 20:00 EDT
Dmitrii E. Makarov, Peter Sollich
Molecules in dense environments, such as biological cells, are subjected to forces that fluctuate both in time and in space. While spatial fluctuations are captured by Lifson-Jackson-Zwanzig’s model of “diffusion in a rough potential”, and temporal fluctuations are often viewed as leading to additional friction effects, a unified view where the environment fluctuates both in time and in space is currently lacking. Here we introduce a discrete-state model of a landscape fluctuating both in time and in space. Importantly, the model accounts for the back-reaction of the diffusing particle on the landscape. As a result we find, surprisingly, that many features of the observable dynamics do not depend on the temporal fluctuation timescales and are already captured by the model of diffusion in a rough potential, even though this assumes a static energy landscape.
Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph), Chemical Physics (physics.chem-ph)
Nonequilibrium transport through the Hubbard dimer
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Yaroslav Pavlyukh, Riku Tuovinen
We apply a computationally efficient approach to study the time- and energy-resolved spectral properties of a two-site Hubbard model using the nonequilibrium Green’s function formalism. By employing the iterative generalized Kadanoff-Baym ansatz ($ i$ GKBA) within a time-linear framework, we avoid the computational cost of solving the full two-time Kadanoff-Baym equations. Spectral information is extracted by coupling the system to multiple narrow-band leads, establishing a direct analogy to photoemission experiments. Our results reveal correlation-induced shifts and broadenings of spectral features, along with a suppression of transient current oscillations. This approach provides a promising avenue for analyzing correlated electron dynamics in open quantum systems.
Strongly Correlated Electrons (cond-mat.str-el)
Discovery of the Type-II Superconductor Ta$_4$Rh$2$C${1-δ}$ with a High Upper Critical Field
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-04 20:00 EDT
KeYuan Ma, Sara López-Paz, Karolina Gornicka, Harald O. Jeschke, Tomasz Klimczuk, Fabian O. von Rohr
We report on the discovery of superconductivity in the previously unknown compound Ta$ _4$ Rh$ _2$ C$ _{1-\delta}$ . Ta$ _4$ Rh$ _2$ C$ _{1-\delta}$ crystallizes in the $ \eta$ -carbide structure type, in the cubic space group $ Fd\bar{3}m$ (No.227) with a unit cell parameter of $ a = $ 11.7947 Å. Temperature-dependent magnetic susceptibility, resistivity, and specific heat capacity measurements reveal that Ta$ _4$ Rh$ 2$ C$ {1-\delta}$ is a type-II bulk superconductor with a critical temperature of $ T{\rm c}$ = 6.4 K, and a normalized specific heat jump $ \Delta C/\gamma T{\rm c}$ = 1.56. Notably, we find Ta$ _4$ Rh$ 2$ C$ {1-\delta}$ has a high upper critical field of $ \mu_0 H{\rm c2}{\rm (0)}$ = 17.4 T, which is exceeding the BCS weak coupling Pauli limit of $ \mu_0 H{\rm Pauli}$ = 11.9 T.
Superconductivity (cond-mat.supr-con)
Phys. Rev. Research 7, 023147 (2025)
First-Principles and Machine Learning Investigation of the Structural and Optoelectronic Properties of Dodecaphenylyne: A Novel Carbon Allotrope
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Kleuton A. L. Lima, Jose A. S. Laranjeira, Nicolas F. Martins, Julio R. Sambrano, Alexandre C. Dias, Luiz A. Ribeiro Junior, Douglas S. Galvao
We report the computational discovery and characterization of Dodecaphenylyne (DP), a novel carbon allotrope with a distinctive geometric arrangement. DP structural, thermodynamic, mechanical, electronic, and optical properties were evaluated using density functional theory and a machine learning interatomic potential trained explicitly for this material. The formation energy of -7.98 eV/atom indicates high thermodynamic stability, further supported by the absence of imaginary phonon modes and the preservation of structural integrity up to 1000 K in ab initio molecular dynamics simulations. Mechanical analysis reveals high in-plane stiffness with directional dependence: Young’s modulus values of 469.09 GPa and 600.41 GPa along the x and y directions, respectively. Electronic band structure and projected density of states analyses confirm the DP semiconducting character. Calculations of carrier mobility using the deformation potential theory reveal pronounced anisotropy, with maximum values reaching up to $ 30.6 \times 10^4$ cm$ ^2$ /V$ \cdot$ s (electrons, e) and $ 8.4 \times 10^4$ cm$ ^2$ /V$ \cdot$ s (holes, h), much higher than the observed for other 2D materials. DP also exhibits anisotropic optical absorption in the visible and ultraviolet spectrum, highlighting its potential for optoelectronic applications.
Materials Science (cond-mat.mtrl-sci)
Atomic-scale mapping of interfacial phonon modes in epitaxial YBa2Cu3O7-δ / (La,Sr)(Al,Ta)O3 thin films: The role of surface phonons
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-04 20:00 EDT
Joaquin E. Reyes Gonzalez, Charles Zhang, Rainni K. Chen, John Y.T. Wei, Maureen J. Lagos
We investigate the behavior of phonons at the epitaxial interface between YBa2Cu3O7-{\delta} thin film and (La,Sr)(Al,Ta)O3 substrate using vibrational electron energy loss spectroscopy. Interfacial phonon modes with different degrees of scattering localization were identified. We find evidence that surface contributions from the surrounding environment can impose additional scattering modulation into local EELS measurements at the interface. A method to remove those contributions is then used to isolate the phonon information at the interface. This work unveils interfacial phonon modes in a high-Tc cuprate superconductor, that are not accessible with traditional phonon spectroscopy techniques, and provides a method for probing interfacial phonons in complex oxide heterostructures.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
17 pages, 4 figures
A General Approach to the Shape Transition of Run-and-Tumble Particles: The 1D PDMP Framework for Invariant Measure Regularity
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-04 20:00 EDT
Run-and-tumble particles (RTPs) have emerged as a paradigmatic example for studying nonequilibrium phenomena in statistical mechanics. The invariant measure of a wide class of RTPs subjected to a potential possesses a density, which is continuous when tumble rates are high and discontinuous when they are low. This key feature is known as shape transition. By comparison with the Boltzmann distribution characteristic of thermodynamic equilibrium, this constitutes a qualitative indicator of the relative closeness (continuous density) or strong deviation (discontinuous density) from the equilibrium setting. Furthermore, the points where the density diverges represent typical states where the system spends most of its time in the low tumble rate regime. Building on and extending existing results concerning the regularity of the invariant measure of one-dimensional piecewise-deterministic Markov processes (PDMPs), we show how to characterize the shape transition even in situations where the invariant measure cannot be computed explicitly. Our analysis confirms shape transition as a robust, general feature of RTPs subjected to a potential. We improve the qualitative picture of the degree to which general RTPs deviate from equilibrium and identify their typical states in the low tumble rate regime. We also refine the regularity theory for the invariant measure of one-dimensional PDMPs.
Statistical Mechanics (cond-mat.stat-mech), Probability (math.PR)
Energy minima and ordering in ferromagnets with quenched randomness
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-04 20:00 EDT
Energy minimization at T=0 and Monte Carlo simulations at T>0 have been performed for 2D and 3D random-field and random-anisotropy systems of up to 100 million classical spins. The main finding is that 3D random-anisotropy systems magnetically order on lowering temperature, contrary to the theoretical predictions based on the Imry-Ma argument. If random-anisotropy is stronger than the exchange, which can be the case in sintered materials, the system still orders but the magnetization is strongly reduced and there is a large spin-glass component in the spin state, the heat capacity having a cusp instead of a divergence. 3D random-field systems do not magnetically order on lowering temperature but rather freeze into the correlated spin-glass state. Here, although magnetized local energy minima have lower energies than non-magnetized ones, magnetic ordering is prevented by singularities pinned by the random field.
Statistical Mechanics (cond-mat.stat-mech)
12 PR pager, 13 figure captions
Ultrahigh-Q Torsional Nanomechanics through Bayesian Optimization
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Atkin D. Hyatt, Aman R. Agrawal, Christian M. Pluchar, Charles A. Condos, Dalziel J. Wilson
Recently it was discovered that torsion modes of strained nanoribbons exhibit dissipation dilution, giving a route to enhanced torque sensing and quantum optomechanics experiments. As with all strained nanomechanical resonators, an important limitation is bending loss due to mode curvature at the clamps. Here we use Bayesian optimization to design nanoribbons with optimal dissipation dilution of the fundamental torsion mode. Applied to centimeter-scale Si$ _3$ N$ _4$ nanoribbons, we realize $ Q$ factors exceeding 100 million and $ Q$ -frequency products exceeding $ 10^{13}$ Hz at room temperature. The thermal torque sensitivity of the reported devices is at the level of $ 10^{-20};\text{N},\text{m}/\sqrt{\text{Hz}}$ and the zero point angular displacement spectral density is at the level of $ 10^{-10};\text{rad}/\sqrt{\text{Hz}}$ ; they are moreover simple to fabricate, have high thermal conductivity, and can be heavily mass-loaded without diminishing their $ Q$ , making them attractive for diverse fundamental and applied weak force sensing tasks.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
6 pages, 4 figures
Sodium-Decorated P-C3N: A Porous 2D Framework for High-Capacity and Reversible Hydrogen Storage
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Jose A. S. Laranjeira, Nicolas F. Martins, Kleuton A. L. Lima, Lingtao Xiao, Xihao Chen, Luiz A. Ribeiro Junior, Julio R. Sambrano
The development of reversible hydrogen storage materials has become crucial for enabling carbon-neutral energy systems. Based on this, the present work investigates the hydrogen storage on the sodium-decorated P-C$ _3$ N (Na@P-C$ _3$ N), a porous carbon nitride monolayer recently proposed as a stable semiconductor. First-principles calculations reveal that Na atoms preferentially adsorb with an adsorption energy of -4.48eV, effectively suppressing clusterization effects. Upon decoration, the system becomes metallic, while \textit{ab initio} molecular dynamics simulations confirm the thermal stability of Na@P-C$ _3$ N at 300K. Hydrogen adsorption on Na@P-C$ _3$ N occurs through weak physisorption, with energies ranging from -0.18 to -0.28eV, and desorption temperatures between 231 and 357K. The system can stably absorb 16 H$ _2$ molecules per unit cell, corresponding to a gravimetric storage capacity of 9.88~wt%, surpassing the U.S. Department of Energy target. These results demonstrate that Na@P-C$ _3$ N is a promising candidate for lightweight, stable, and reversible hydrogen storage.
Materials Science (cond-mat.mtrl-sci)
OLi3-decorated Irida-graphene for High-capacity Hydrogen Storage: A First-principles Study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Jose A. S. Laranjeira, Warda Elaggoune, Nicolas F. Martins, Xihao Chen, Julio R. Sambrano
Efficient hydrogen storage in solid-state materials is essential for next-generation energy systems, yet achieving a high gravimetric capacity with optimal adsorption characteristics remains a critical challenge. Although Li-decorated irida-graphene (IG) has shown promising hydrogen storage potential, its capacity is limited to $ \sim$ 7wt%, which, despite exceeding the U.S. DOE target, remains inadequate for large-scale applications. Additionally, Li clustering over extended cycles may compromise adsorption efficiency and structural stability. In this study, we employ first-principles calculations to investigate the hydrogen storage potential of IG decorated with superalkali OLi$ _3$ clusters, aiming to enhance the adsorption capacity and stability for advanced hydrogen storage technologies. Our findings show that the OLi$ _3$ clusters exhibit a significant binding energy of -3.24 eV, which highlights its strong interaction with the IG. OLi$ _3$ @IG complex can host up to 12H$ _2$ molecules, with optimal maximum storage capacity of 10.00 wt%. Additionally, the release temperature (T$ _R$ ) and \textit{ab initio} molecular dynamics (AIMD) simulations indicate that H$ _2$ molecules can be efficiently released at operating temperatures under ambient conditions. These results highlight the potential of OLi$ _3$ -decorated irida-graphene as a promising candidate for reversible hydrogen storage.
Materials Science (cond-mat.mtrl-sci)
Cell-Scale Dynamic Modeling of Membrane Interactions with Arbitrarily Shaped Particles
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Didarul Ahasan Redwan, Justin Reicher, Xin Yong
Modeling membrane interactions with arbitrarily shaped colloidal particles, such as environmental micro- and nanoplastics, at the cell scale remains particularly challenging, owing to the complexity of particle geometries and the need to resolve fully coupled translational and rotational dynamics. Here, we present a force-based computational framework capable of capturing dynamic interactions between deformable lipid vesicles and rigid particles of irregular shapes. Both vesicle and particle surfaces are represented using triangulated meshes, and Langevin dynamics resolves membrane deformation alongside rigid-body particle motion. Adhesive interactions between the particle and membrane surfaces are modeled using two numerical schemes: a vertex-to-vertex mapping and a vertex-to-surface projection. The latter yields more accurate wrapping energetics, as demonstrated by benchmark comparisons against ideal spheres. The dynamic simulations reveal that lower particle-to-vesicle mass ratios facilitate frequent particle reorientation and complete membrane wrapping, while higher mass ratios limit orientation changes and stabilize partial wrapping. To illustrate the framework’s versatility, we simulate interactions involving cubical, rod-like, bowl-shaped, and tetrahedral particles with spherical, cigar-shaped, or biconcave vesicles. This generalizable modeling approach enables predictive, cell-scale studies of membrane-particle interactions across a wide range of geometries, with applications in environmental biophysics and nanomedicine.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
21 pages, 8 figures
Multi-mode cooling of a Bose-Einstein condensate with linear quantum feedback
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-04 20:00 EDT
Zain Mehdi, Matthew L. Goh, Matthew J. Blacker, Joseph J. Hope, Stuart S. Szigeti
We theoretically investigate measurement-based feedback control over the motional degrees of freedom of an oblate quasi-2D atomic Bose-Einstein condensate (BEC) subject to continuous density monitoring. We develop a linear-quadratic-Gaussian (LQG) model that describes the multi-mode dynamics of the condensate’s collective excitations under continuous measurement and control. Crucially, the multi-mode cold-damping feedback control we consider uses a realistic state-estimation scheme that does not rely upon a particular model of the atomic dynamics. We present analytical results showing that collective excitations can be cooled to below single-phonon average occupation (ground-state cooling) across a broad parameter regime and identify the conditions under which the lowest steady-state phonon occupation is asymptotically achieved. Further, we develop multi-objective optimization methods that explore the trade-off between cooling speed and the final energy of the cloud and provide numerical simulations demonstrating the ground-state cooling of the lowest ten motional modes above the condensate ground state. Our investigation provides concrete guidance on the feedback control design and parameters needed to experimentally realize a feedback-cooled BEC.
Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
Spin-chain multichannel Kondo model via image impurity boundary condition
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Jordan Gaines, Guangjie Li, Jukka Väyrynen
One of the signature observables for the electronic multichannel Kondo model is the impurity entropy, which was claimed to be found in $ J_1$ -$ J_2$ Heisenberg chain with open boundary condition (OBC) and periodic boundary condition (PBC), respectively for the one-channel and two-channel case. However, it is not clear how to generalize OBC and PBC in Heisenberg chains to find the multichannel Kondo impurity entropy with more than two channels. In this paper, we demonstrate that the correct boundary condition for realizing multichannel Kondo physics in Heisenberg chains is the image impurity boundary condition (IIBC), which yields the expected impurity entropy, $ \ln[(\sqrt{5}+1)/2]$ for the three-channel case and $ \ln\sqrt{3}$ for the four-channel case. Moreover, the IIBC reduces to OBC for the one-channel case and to PBC for the two-channel case. With IIBC, the finite-size scaling of the impurity entropy and the total spin both match the finite-temperature correction in the electronic multichannel Kondo model. Additionally, we show that the XXZ anisotropy reduces the impurity entropy through a power law of the effective Luttinger liquid parameter.
Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 5 figures
Highly reliable, ultra-wideband, isolator-free quantum-dot mode-locked frequency combs for optical interconnects beyond 3.2Tb/s
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Shujie Pan, Victoria Cao, Yiheng Feng, Dingyi Wu, Jie Yan, Junjie Yang, Chao Zhao, Xi Xiao, Siming Chen
Quantum dot mode-locked laser-based optical frequency combs are emerging as a critical solution for achieving low-cost, high-efficiency, and large-capacity optical interconnects. The practical implementation of wavelength division multiplexing interconnects necessitates a temperature-stable OFC source with a minimum 100 GHz channel spacing to enable high-bandwidth modulation while mitigating the complexity of optical filtering and detection. By leveraging the advanced co-doping technique and a colliding pulse mode-locking scheme, here, we report a compact, ultra-wideband, highly reliable, isolator-free 100 GHz-spacing InAs/GaAs QD OFC source operating up to a record temperature of 140 °C. The comb source delivers a record 3 dB optical bandwidth of 14.312 nm, containing flat-top comb lines, each supporting 128 Gb/s PAM-4 modulation, which results in a total throughput of 3.328 Tb/s with an extremely low power consumption of 0.394 pJ/bit at 25°C. Performance remains stable at 85 °C, with negligible degradation of device critical metrics. Remarkably, accelerated aging tests under harsh conditions (85 °C with 8x threshold current injection) revealed a mean time to failure of approximately 207 years. The QD OFC source demonstrated in this work, for the first time, establishes a concrete link between fundamental research on comb sources and their practical deployment in next-generation, high-density optical interconnect systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Optics (physics.optics)
Revisiting the Mechanisms of Thermal Transport in Vacancy-Defective Silicon
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Xueyan Zhu, Jin Yang, J. Shiomi, Cheng Shao
Understanding heat conduction in defective silicon is crucial for electronics and thermoelectrics. Conventional understanding relies on phonon gas picture, treating defects as scattering centers that reduce phonon lifetimes without altering frequencies and group velocities. We go beyond phonon gas picture by employing Wigner transport equation to investigate heat conduction in vacancy-defected silicon. Our findings reveal that while thermal conduction in pristine silicon stems mainly from particle-like propagation of vibrational modes, wave-like tunnelling becomes increasingly significant in the presence of vacancies. Contrary to the conventional belief that defects only perturb mode lifetimes, we demonstrate that vacancies also diminish velocity operators, a dominant factor in thermal conductivity reduction, surpassing even the effect of lifetime shortening. Furthermore, incorporating anharmonic frequencies and interatomic force constants shows that while anharmonicity suppresses thermal conductivity in pristine silicon, this effect weakens with vacancy concentration and reverses to enhance conductivity. These findings challenge conventional knowledge and provide new insights into thermal conduction in defective materials.
Materials Science (cond-mat.mtrl-sci)
Reconstructing the wavefunction of magnetic topological insulators MnBi2Te4 and MnBi4Te7 using spin-resolved photoemission
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Xue Han, Jason Qu, Hengxin Tan, Zicheng Tao, Noah M. Meyer, Patrick S. Kirchmann, Yanfeng Guo, Binghai Yan, Zhi-Xun Shen, Jonathan A. Sobota
Despite their importance for exotic quantum effects, the surface electronic structure of magnetic topological insulators MnBi2Te4 and MnBi4Te7 remains poorly understood. Using high-efficiency spin- and angle-resolved photoemission spectroscopy, we directly image the spin-polarization and orbital character of the surface states in both compounds and map our observations onto a model wavefunction to describe the complex spin-orbital texture, which solidifies our understanding of the surface band structure by establishing the single-band nature of the most prominent states. Most importantly, our analysis reveals a new mechanism for reducing the magnetic gap of the topological surface states based on the orbital composition of the wavefunction.
Materials Science (cond-mat.mtrl-sci)
Anisotropic superconducting gap probed by $^{125}$Te NMR in noncentrosymmetric Sc$_6M$Te$_2$ ($M$ = Fe, Co)
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-04 20:00 EDT
Kanako Doi, Hayase Takei, Yusaku Shinoda, Yoshihiko Okamoto, Daigorou Hirai, Koshi Takenaka, Taku Matsushita, Yoshiaki Kobayashi, Yasuhiro Shimizu
The superconducting gap symmetry is investigated by $ ^{125}$ Te NMR measurements on Sc$ _6M$ Te$ _2$ ($ M$ = Fe, Co) without spatial inversion symmetry. The spin susceptibility obtained from the Knight shift $ K$ is suppressed below the superconducting transition temperature, while leaving a finite value down to the lowest temperature ($ \simeq 0.4$ K). The nuclear spin-lattice relaxation rate $ 1/T_1$ follows a power law against temperature $ T$ without showing a coherence peak characteristic of the isotropic gap. The result implies a pairing admixture or a residual density of states under magnetic field. The normal metallic state has a Korringa scaling relation between $ 1/T_1T$ and the Knight shift, reflecting a weak electron correlation.
Superconductivity (cond-mat.supr-con)
7 pages, 7 figures
Phys. Rev. B. 111, 214502 (2025)
Identification of gapless phases by squaring a twist operator
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Hang Su, Yuan Yao, Akira Furusaki
We propose a general necessary condition for a spin chain with SO(3) spin-rotation symmetry to be gapped. Specifically, we prove that the ground state(s) of an SO(3)-symmetric gapped spin chain must be spin singlet(s), and the expectation value of the square of a twist operator asymptotically approaches unity in the thermodynamic limit, where finite-size corrections are inversely proportional to the square root of the system size. This theorem provides (i) supporting evidence for various conjectured gapped phases, and (ii) a sufficient criterion for identifying gapless spin chains. We verify our theorem by numerical simulations for a variety of spin models and show that it offers a novel efficient way to identify gapless phases in spin chains with spin-rotation symmetry.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th), Mathematical Physics (math-ph)
6 pages, 3 figures
Electronic structures and magnetism in van der Waals flat-band material Ni${3}$GeTe${2}$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Yuanji Xu, Xintao Jin, Haoyuan Tang, Fuyang Tian
The study of magnetism in two-dimensional materials has garnered significant interest, driven by fundamental investigations into low-dimensional magnetic phenomena and their potential for applications in spintronic devices. Through dynamical mean-field theory calculations, we demonstrate that Ni$ _{3}$ GeTe$ _{2}$ exhibits flat-band characteristics resulting from the geometric frustration of its layered triangular lattice. These flat bands are further renormalized due to moderate electronic correlation. Our calculations reveal that the magnetic order of Ni atoms is significantly influenced by both the Coulomb interaction and Hund’s coupling, indicating that the physics of Ni atoms is situated in an intermediate region between Hundness and Mottness. Additionally, our results show that Ni atoms experience significant spin fluctuations in their local moments, maintaining paramagnetism at low temperatures. Furthermore, we investigate the effect of vacancies, finding a substantial suppression of the density of states at the Fermi level. The physical mechanisms uncovered by our study provide a comprehensive understanding of the novel properties exhibited by this type of material.
Strongly Correlated Electrons (cond-mat.str-el)
Sequential binding-unbinding based specific interactions highlight exchange dynamics and size distribution of condensates
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Understanding the mechanisms of formation of organelles and biomolecular condensates via liquid-liquid phase separation is a topic of great interest. It is reasonable to assume that the formation of protein-specific condensates inside a crowded, multicomponent cellular environment requires specific protein-protein interactions with lifetimes longer than non-specific protein-protein interactions. These longer-lived, specific interactions can arise through complex protein binding and unbinding pathways. In this work, we investigate single-step and sequential multi-step mechanisms for protein binding-unbinding interactions and model the lifetimes of such interactions in a heuristic manner. We show that while similar average interaction lifetimes can be achieved when binding-unbinding follows a single-step or a sequential multi-step process, the two processes result in two distinct lifetime distributions: exponential and truncated power-law, respectively. We then combine this model with Brownian dynamics simulations to elucidate the impact of these distinct lifetime distributions on condensate dynamics. Our model qualitatively captures important features of condensates, such as their fluidic nature, aging in protein interactions and its impact on the exchange dynamics, and the size distribution of condensates. In a nutshell, our model unravels how specificity in protein binding-unbinding interaction pathways, resulting in unique interaction lifetime distributions, is a key factor shaping the physical properties of biomolecular condensates.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
Navigating Phase Transitions with Path-Finding Algorithms: A Strategic Approach to Replica Exchange Monte Carlo
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-04 20:00 EDT
Akie Kowaguchi, Katsuhiro Endo, Kentaro Nomura, Shuichi Kurabayashi, Paul E. Brumby, Kenji Yasuoka
The replica exchange method is a powerful tool for overcoming slow relaxation in molecular simulations, but its efficiency depends strongly on the choice of the number and interval of replicas and their exchange probabilities. Here, we propose a new optimization scheme based on the Dijkstra algorithm that constructs an optimal exchange path by representing replicas and their exchange probabilities as a graph. Inspired by path-finding techniques widely used in computer science, including applications in game algorithms, our approach ensures that transitions follow a minimum entropy gradient path and effectively speeds up sampling even in systems exhibiting slow relaxation near critical points or phase transition regions. The method provides a systematic way to improve replica exchange efficiency and offers new insights into the control of relaxation dynamics, as demonstrated through applications to the solid-liquid phase transition of the Lennard-Jones bulk system.
Statistical Mechanics (cond-mat.stat-mech), Computational Physics (physics.comp-ph)
7 pages
Universal band center model for the HER activity of non-metal site
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Ruixin Xu, Shiqian Cao, Tingting Bo, Yanyu Liu, Wei Zhou
In this work, the hydrogen evolution reaction activities of non-metal sites in the transition metal dichalcogenides with the stoichiometry of MX2 are investigated using the first principles calculations. The trained machine learning model demonstrates that the pz band center, bandgap, and period effect are the key factors influencing the HER activity of MX2. Furthermore, it also reveals that the observed non-scaling law between the pz band center and HER activity in the semiconductor-like materials originates from the bandgap-induced downshift of bonding and antibonding states. In addition to the bandgap, the intrinsic p orbital energy level of the non-metal atoms also contributes to the periodic variation of pz band center. Extended calculations indicate that the descriptor is equally applicable to the other catalysts, suggesting its universality in predicting the HER activity of non-metal sites.
Materials Science (cond-mat.mtrl-sci)
Phonon-Induced Current Noise in Single-Walled Carbon Nanotubes across the Ballistic-Diffusive Crossover
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Aina Sumiyoshi, Takahiro Yamamoto
We theoretically elucidate the system length ($ L$ ) dependence of phonon-induced current noise in carbon nanotubes at room temperature over a broad range, encompassing the quantum ballistic and classical diffusive regimes. The power spectral density for the current noise is maximally enhanced when $ L$ is comparable to the mean free path $ L_0$ of an electron. In the ballistic limit of $ L/L_0\ll 1$ , the power spectral density increases in proportion to $ L$ , whereas in the diffusive limit of $ L/L_0\gg 1$ , it shows a power-law decay $ L^{-\alpha}$ with a scaling parameter $ \alpha=3.81$ . The noise decay for single-walled carbon nanotubes is faster than that previously predicted based on a simple model because of the various electron-phonon scattering processes and the complex energy dependence of the phonon relaxation time.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 5 fugures
Confinement-induced resonances for the creation of quasi-1D ultra cold gases of alkali–alkaline-earth dimers
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-04 20:00 EDT
Lorenzo Oghittu, Premjith Thekkeppatt, Nirav P. Mehta, Seth T. Rittenhouse, Klaasjan van Druten, Florian Schreck, Arghavan Safavi-Naini
We theoretically investigate the role of confinement-induced resonances (CIRs) in low-dimensional ultracold atomic mixtures for the formation of weakly bound dimers. To this end, we examine the scattering properties of a binary atomic mixture confined by a quasi-one-dimensional (quasi-1D) potential. In this regime, the interspecies two-body interaction is modeled as an effective 1D zero-range pseudopotential, with a coupling strength $ g_\mathrm{1D}$ derived as a function of the three-dimensional scattering length $ a$ . This framework enables the study of CIRs in harmonically confined systems, with particular attention to the case of mismatched transverse trapping frequencies for the two atomic species. Finally, we consider the Bose-Fermi mixture of $ ^{87}$ Rb and $ ^{87}$ Sr, and identify values of the experimentally accessible parameters for which CIRs can be exploited to create weakly bound molecules.
Quantum Gases (cond-mat.quant-gas)
11 pages, 4 figures
Emergent rigidity percolation of five-fold aggregates enables controllable glass properties
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Wei Chu, Zheng Wang, Christopher Ness, Konrad Samwer, Alessio Zaccone, Lina Hu
Metallic glasses possess outstanding mechanical and physical properties, making them promising candidates for advanced structural and functional applications; however, the lack of understanding and control over their glass transition and solidification processes remains a significant barrier to practical design. The glass transition from liquid to amorphous solid has remained an open problem in physics despite many theories and recent advances in computational efforts. The question of identifying a clear and well-defined diverging length scale accompanying the glass transition has remained unanswered, as has the nature of the transition and, indeed, the presence of a transition at all, as opposed to a mere dynamical crossover. Here we answer these questions using numerical results and theoretical analysis showing that, in atomic (metallic) glass formers, the glass transition coincides with, and is caused by, a continuous rigidity percolation transition from a liquid-like to a solid-like material. The transition occurs as five-fold symmetric atomic clusters progressively aggregate, forming a system-spanning rigid network that marks the onset of mechanical stability. This percolation-driven rigidity growth is accompanied by a sharp increase in the shear modulus G’, indicating the emergence of macroscopic solid-like behavior. Beyond this point, which coincides with the Maxwell isostatic point of the percolating structure, dynamical arrest or “freezing-in” prevents further evolution. The long-sought diverging length scale is thus identified as the percolation-driven growth of rigid five-fold clusters, providing a direct link between local structural motifs and macroscopic mechanical properties at the glass transition. These insights offer practical routes to rationally engineer metallic glasses with targeted mechanical stiffness, hardness, and toughness.
Soft Condensed Matter (cond-mat.soft), Disordered Systems and Neural Networks (cond-mat.dis-nn), Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech), Chemical Physics (physics.chem-ph)
Steady state and relaxation dynamics of run and tumble particles in contact with a heat bath
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-04 20:00 EDT
We study the relaxation dynamics of a run and tumble particle in a one-dimensional piecewise linear potential $ U(x)=b|x|$ , from delta-function initial conditions at $ x=0$ to steady state. In addition to experiencing active telegraphic noise, the particle is in contact with a heat bath at temperature $ T$ that applies white thermal noise. We find that the position distribution of the RTP is described by a sum of two distributions (“modes”), each of which of the form $ P(x,t\to\infty)\sim e^{-\lambda_i|x|}$ ($ i=1,2$ ) at steady state. The two modes are dynamically coupled: At very short times ($ t\to 0$ ), each mode stores half of the probability, and exhibits thermal diffusive spreading with a Gaussian profile. With progressing time and evolution toward steady state, the partition of probability between the modes becomes increasingly uneven and, depending on the model parameters, the mode with the smaller value of $ \lambda_i$ may carry an overwhelming majority of the probability. Moreover, we identify that the characteristic relaxation time of each mode is $ \tau_i=(\lambda_i^2T)^{-1}$ , which implies that the minority mode also relaxes much faster than the dominant one. A more detailed analysis reveals that $ \tau_i$ is characteristic of the mode relaxation only close to the origin at the core of the distribution, while further away it increases linearly with $ |x|$ as if a relaxation front is propagating at constant speed $ v_i^\ast=2\sqrt{T/\tau_i}$ in the system. The rate of non-equilibrium entropy production can be related to the two-mode splitting of the probability distribution and be expressed in terms of their correlation-lengths $ \lambda_i$ and their contributions to the steady state distribution.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
22 pages, 6 figures. Accepted for publication in Phys. Rev. E
Long-range electrical conductivity in non-$π$-conjugated organic molecular materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
H. Mager, A. A. Butkevich, S. Klubertz, S. V. Haridas, O. Shyshov, V. C. Wakchaure, J. Borstelmann, I. Michalsky, M. García-Iglesias, V. Rodríguez, D. González-Rodríguez, A. R. A. Palmans, M. Kivala, M. von Delius, M. Kemerink
Electronic conductivity in organic materials is well-established. Moreover, semiconductive or metallic behavior in (quasi) 0-, 1-, 2- and 3-dimensional carbon-based materials has been demonstrated and understood and is nowadays widely applied in commercial devices. Despite the large structural variety, these materials commonly have an extended $ \pi$ -system, formed by sp2-hybridized carbon atoms, which is responsible for the conductivity. Here, we present a class of organic molecular materials that, despite the absence of an extended $ \pi$ -system, show a distinct direct current conductivity in quasi-1D supramolecular stacks of small organic molecules. Long-range conductivity takes place by removal of an electron from the highest occupied molecular orbital, i.e. oxidation, followed by charge transfer between neighboring molecules. In thin-film devices, the resulting transport band becomes energetically accessible to charges from the contacts by interfacial dipoles stemming from a dipolar group in the molecule. Long-range order in the form of the supramolecular polymers with lengths exceeding several micrometers enhances the macroscopic conductivity but is not essential. The results presented herein show a new way to incorporate electronic functionality in organic materials and present a new class of organic conductors that lack the extended $ \pi$ -electron-system of conventional organic semiconductors.
Materials Science (cond-mat.mtrl-sci)
Reentrant localization in a quasiperiodic chain with correlated hopping sequences
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-06-04 20:00 EDT
Sourav Karmakar, Sudin Ganguly, Santanu K. Maiti
Quasiperiodic systems are known to exhibit localization transitions in low dimensions, wherein all electronic states become localized beyond a critical disorder strength. Interestingly, recent studies have uncovered a reentrant localization (RL) phenomenon: upon further increasing the quasiperiodic disorder strength beyond the localization threshold, a subset of previously localized states can become delocalized again within a specific parameter window. While RL transitions have been primarily explored in systems with simple periodic modulations, such as dimerized or long-range hopping integrals, the impact of more intricate or correlated hopping structures on RL behavior remains largely elusive. In this work, we investigate the localization behavior in a one-dimensional lattice featuring staggered, correlated on-site potentials following the Aubry-André-Harper model, along with off-diagonal hopping modulations structured according to quasiperiodic Fibonacci and Bronze Mean sequences. By systematically analyzing the fractal dimension, inverse participation ratio, and normalized participation ratio, we demonstrate the occurrence of RL transitions induced purely by the interplay between quasiperiodic on-site disorder and correlated hopping. Our findings highlight the crucial role of underlying structural correlations in governing localization-delocalization transitions in low-dimensional quasiperiodic systems, where the correlated disorder manifests in both diagonal and off-diagonal terms.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el), Computational Physics (physics.comp-ph), Data Analysis, Statistics and Probability (physics.data-an)
7 pages, 5 figures. Comments are welcome
Chaotic magnetization dynamics in magnetic Duffing oscillator
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Ryo Tatsumi, Takahiro Chiba, Takashi Komine, Hiroaki Matsueda
We propose a magnetic analogy of the Duffing oscillator–magnetic Duffing oscillator–which is characterized by a double-well magnetic potential of a ferromagnet with a uniaxial magnetic anisotropy. Based on the linear stability analysis of the Landau-Lifshitz-Gilbert equation, we show that an external magnetic field applied perpendicular to the magnetic anisotropy field creates an anharmonicity on the magnetic potential, generating homoclinic orbits in the phase space. By evaluating the Lyapunov exponent, we demonstrate that the magnetic Duffing oscillator exhibits chaotic behaviors in the presence of periodically oscillating external forces: Oersted field and spin-orbit torque by considering the ferromagnet/heavy-metal bilayer. We also show that the external magnetic field can be adjusted to generate or modify homoclinic orbits, thereby controlling the parameter range of the oscillating external forces that induce chaos. This work deepens our understanding of chaotic magnetization dynamics by bridging the fields of nonlinear dynamics and spintronics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Chaotic Dynamics (nlin.CD), Applied Physics (physics.app-ph)
12 pages, 10 figures
Phys. Rev. E, 111, 064202 (2025)
Spin-orbit interaction in square core-shell nanowires
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Anna Sitek, Tudor Gabriel Dumitru, Sigurdur I. Erlingsson, Andrei Manolescu
We theoretically investigate the spin-orbit interaction of electrons confined in the outer regions of square core-shell nanowires. The polygonal cross section leads to the accumulation of low-energy electrons in the corners and the formation of a significant energy gap that separates these corner-localized states from higher-energy states localized along the sides. We show that the low-energy states behave like the states of independent quantum wires, while the higher-energy states exhibit features characteristic of coupled wires.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
25th International Conference on Transparent Optical Networks (ICTON), Barcelona, July 2025
Probing the semiconductor-to-dirac semimetal transition in Na-Sb-Bi alloys with x-ray Compton scattering
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Aki Pulkkinen, Veenavee Nipunika Kothalawala, Kosuke Suzuki, Bernardo Barbiellini, Johannes Nokelainen, Wei-Chi Chiu, Bahadur Singh, Hsin Lin, Alok K. Pandey, Naoaki Yabuuchi, Naruki Tsuji, Yoshiharu Sakurai, Hiroshi Sakurai, Ján Minár, Arun Bansil
We discuss electron redistribution during the Semiconductor-to-Dirac Semimetal transition in Na-Sb-Bi alloys using x-ray Compton scattering experiments combined with first-principles electronic structure modeling. A robust signature of the semiconductor-to-Dirac semimetal transition is identified in the spherically averaged Compton profile. We demonstrate how the number of electrons involved in this transition can be estimated to provide a novel descriptor for quantifying the strength of spin-orbit coupling responsible for driving the transition. The associated theoretical deviation of the Born charge of Na in Na$ _3$ Bi from the expected ionic charge of +1 is found to be consistent with the corresponding experimental value of about 10%. Our study also shows the sensitivity of the Compton scattering technique toward capturing the spillover of Bi 6p relativistic states onto Na sites.
Materials Science (cond-mat.mtrl-sci)
Inertia-driven propulsion of asymmetric spinner-dimers at moderate Reynolds numbers
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Zaiyi Shen, Dongfang Fu, Juho Lintuvuori
We investigate the translational motion of rotating colloidal systems at moderate Reynolds numbers (Re), focusing on particle dimers in snowman-like configurations under three scenarios: (i) two co-rotating spheres driven by an external field, (ii) two counter-rotating spheres driven by an internal torque as a swimmer, and (iii) a single rotating spinner with a passive sphere for cargo delivery, using hydrodynamic simulations. In all the three cases, the particles are bound together hydrodynamically, and the purely rotational motion of the spinners produces a net propulsion of the dimers along the axis of rotation due to a symmetry breaking. We demonstrate tunable dynamics, where the propulsion direction of the co-rotating dimer can be reversed by tuning the aspect ratio and Reynolds number, as well as cargo transport where a dimer consisting of a single spinner and a passive cargo particle can have a sustained locomotion due to broken head-to-tail symmetry of the overall flow fields. These findings highlight the critical role of inertia in creating locomotion from rotational motion and offer new avenues for controlling and optimizing translational motion in colloidal assemblies through rotational degrees of freedom.
Soft Condensed Matter (cond-mat.soft), Fluid Dynamics (physics.flu-dyn)
9 pages, 7 figures
Soft Matter 21, 4021-4028 (2025)
Thermodynamic Uncertainty Relation in Hybrid Normal-Superconducting Systems: The Role of superconducting coherence
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Franco Mayo, Nahual Sobrino, Rosario Fazio, Fabio Taddei, Michele Governale
We study the violation of thermodynamic uncertainty relations (TURs) in hybrid superconducting systems consisting of one superconducting and two normal leads coupled to a central region containing localized levels, focusing on the role of quantum coherence. We first study the simplest setup yielding TUR violations, where the central region is a single-level quantum dot and only one normal lead is connected.
In addition to the {\it classical} TUR, we consider an alternative formulation recently derived for coherent conductors. We find even the latter TUR is violated (although by a smaller extent) as a result of the macroscopic coherence related to the superconducting condensate. To support this conclusion, we connect the second normal lead as a dephasing probe, demonstrating that the violation is directly correlated with the superconducting coherence, as measured by the dot’s pair amplitude. When the central region is a Cooper-pair splitter, crossed Andreev processes introduce nonlocal superconducting correlations that further enhance the quantum-TUR violation.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
6 pages, 4 figures
Spatial correlations of charge density wave order across the transition in 2H-NbSe2
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Seokjo Hong, Jaewhan Oh, Woohyun Cho, Soyoung Lee, Colin Ophus, Yeongkwan Kim, Heejun Yang, SungBin Lee, Yongsoo Yang
Charge density waves (CDWs) involve coupled amplitude and phase degrees of freedom, but direct access to local amplitude correlations remains experimentally challenging. Here, we report cryogenic four-dimensional scanning transmission electron microscopy (4D-STEM) measurements of CDW ordering in 2H-NbSe2, enabled by liquid helium-based cooling down to 20 K. By mapping the spatial distribution of CDW superlattice intensities at nanometer-scale resolution and analyzing their autocorrelations, we extract the temperature-dependent correlation length associated with the local amplitude of the CDW order parameter, independent of global phase coherence. Our results reveal that weak short-range amplitude correlations persist above the transition temperature, and grow significantly upon cooling, reaching approximately 150 nm at 20 K. These findings demonstrate clear deviations from mean-field expectations and establish 4D-STEM as a powerful tool for probing spatially inhomogeneous electronic order in quantum materials.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
8 pages, 4 main figures and 3 appendix figures
Simplifying higher-order perturbation theory for ring-shaped Bose-Hubbard systems
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-04 20:00 EDT
In this paper, higher-order perturbation theory is applied and tailored to one-dimensional ring-shaped Bose-Hubbard systems. Spectral and geometrical properties are used to structurally simplify the contributions and reduce computational effort without sacrificing accuracy. For this, a guide for the computation of the individual perturbational orders up to order nine is provided, alongside a both system-specific and parametrization-dependent convergence criterion. The simplification scheme described is found to be applicable to a wider class of Bose-Hubbard systems with different lattice geometries. An exemplary validation of these findings is included in the form of explicit calculations of ground state energies of the three-site Bose-Hubbard system with repulsive on-site interactions. These calculations are successfully checked against numerical computations of exact diagonalization results.
Quantum Gases (cond-mat.quant-gas)
16 pages, 3 figures. Phys. Scr. 2025
Understanding Stability Mechanisms in Single-Atom Alloys with Theory-infused Deep Learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-04 20:00 EDT
Yang Huang, Shih-Han Wang, Shuyi Cao, Luke E. K. Achenie, Hongliang Xin
We present an interpretable deep learning model that enhances the prediction of cohesive energy in transition metal alloys (TMAs) by incorporating cohesion theory into a graph neural network (GNN) framework. The model not only predicts the total cohesive energy-an indicator of crystal stability-but also disentangles its various contributing factors and underlying physical parameters. The physics insights extracted from the model clarify the stability trends of transition metal surfaces across the periodic table. Furthermore, by applying the model to single-atom alloys (SAAs), a class of catalytically significant next-generation TMAs, we analyze and explain the relative stability of monomer/dimer (in-plane symmetry breaking) and top-/sub-layer (out-of-plane symmetry breaking) configurations. These two types of symmetry breaking lead to distinct thermodynamic preferences in SAAs, governed by localized effects (e.g. d-orbital coupling) and delocalized effects (e.g. wavefunction renormalization). The model is thus positioned as a powerful tool for understanding and strategically designing TMAs, enabling the tailored development of materials with improved stability for advanced applications in catalysis and materials science.
Materials Science (cond-mat.mtrl-sci)
Subdiffusion from competition between multi-exponential friction memory and energy barriers
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Anton Klimek, Benjamin A. Dalton, Roland R. Netz
Subdiffusion is a hallmark of complex systems, ranging from protein folding to transport in viscoelastic media. However, despite its pervasiveness, the mechanistic origins of subdiffusion remain contested. Here, we analyze both Markovian and non-Markovian dynamics, in the presence and absence of energy barriers, in order to disentangle the distinct contributions of memory-dependent friction and energy barriers to the emergence of subdiffusive behavior. Focusing on the mean squared displacement (MSD), we develop an analytical framework that connects subdiffusion to multiscale memory effects in the generalized Langevin equation (GLE), and derive the subdiffusive scaling behavior of the MSD for systems governed by multi-exponential memory kernels. We identify persistence and relaxation timescales that delineate dynamical regimes in which subdiffusion arises from either memory or energy barrier effects. By comparing analytical predictions with simulations, we confirm that memory dominates the overdamped dynamics for barrier heights up to approximately $ 2,k_BT$ , a regime recently shown to be relevant for protein folding. Overall, our results advance the theoretical understanding of anomalous diffusion and provide practical tools that are broadly applicable to fields as diverse as molecular biophysics, polymer physics, and active matter systems.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph)
14 pages main text including 6 figures and 11 pages supplementary information (SI) including 4 additional figures
Symmetry-protected electronic metastability in an optically driven cuprate ladder
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Hari Padma, Filippo Glerean, Sophia F. R. TenHuisen, Zecheng Shen, Haoxin Wang, Luogen Xu, Joshua D. Elliott, Christopher C. Homes, Elizabeth Skoropata, Hiroki Ueda, Biaolong Liu, Eugenio Paris, Arnau Romaguera, Byungjune Lee, Wei He, Yu Wang, Seng Huat Lee, Hyeongi Choi, Sang-Youn Park, Zhiqiang Mao, Matteo Calandra, Hoyoung Jang, Elia Razzoli, Mark P. M. Dean, Yao Wang, Matteo Mitrano
Optically excited quantum materials exhibit nonequilibrium states with remarkable emergent properties, but these phenomena are usually transient, decaying on picosecond timescales and limiting practical applications. Advancing the design and control of nonequilibrium phases requires the development of targeted strategies to achieve long-lived, metastable phases. Here, we report the discovery of symmetry-protected electronic metastability in the model cuprate ladder Sr$ _{14}$ Cu$ _{24}$ O$ _{41}$ . Using femtosecond resonant x-ray scattering and spectroscopy, we show that this metastability is driven by a transfer of holes from chain-like charge reservoirs into the ladders. This ultrafast charge redistribution arises from the optical dressing and activation of a hopping pathway that is forbidden by symmetry at equilibrium. Relaxation back to the ground state is hence suppressed after the pump coherence dissipates. Our findings highlight how dressing materials with electromagnetic fields can dynamically activate terms in the electronic Hamiltonian, and provide a rational design strategy for nonequilibrium phases of matter.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
Submitted version. Main text: 27 pages, 6 figures. SI: 36 pages, 19 figures
Nature Materials (2025), advanced online publication (URL: https://www.nature.com/articles/s41563-025-02254-2)
Mesoscopic Helices of Polar Domains in a Quadruple Perovskite
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-04 20:00 EDT
Yang Zhang, Mingyu Xu, Jie Li, Suk Hyun Sung, Sang-Wook Cheong, Weiwei Xie, Ismail El Baggari
A significant effort in condensed matter physics is dedicated to the search for exotic arrangements of electric dipoles. Beyond collinear alignments of electric dipoles, more complex arrangements analogous to magnetic spin textures, such as polar vortices and skyrmions, have been realized. Here we report atomic-scale visualizations of a candidate for helical texture of electric dipoles, the lightly doped quadruple perovskite BiCu$ _{x}$ Mn$ _{7-x}$ O$ _{12}$ . Rather than forming a continuous incommensurate helical structure, this material exhibits a mesoscale ordering of ferroelastic and polar domains. Across domains, bismuth’s polar displacement rotates discretely following a consistent handedness, giving rise to a mesoscale helical pattern. We observe both right-handed and left-handed chiralities associated with helical ordering. The mesoscopic helices of polar order observed in our work would provide an opportunity to realize emergent chiral-optical activity in ferroelectric crystals akin to supramolecular assemblies.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Paramagnetism in spherically confined charged active matter
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-04 20:00 EDT
Balázs Németh, Ronojoy Adhikari
The celebrated theorem of Bohr and van Leeuwen guarantees that a classical charged system cannot have a magnetization in thermal equilibrium. Quantum mechanically, however, a diamagnetic response is obtained. In contrast, we show here that a classical charged active system, consisting of a motile particle confined to the surface of a sphere, has a nonzero magnetization and a paramagnetic response. We numerically sample Langevin trajectories of this system and compare with limiting analytical solutions of the Fokker-Planck equation, at small and large temperatures, to find excellent agreement in the magnetic response. Our Letter suggests experimental routes to controlling and extracting work from charged active matter.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
6 pages, 3 figures. Accepted for publication as a Letter in Physical Review Research
Creating and melting a supersolid by heating a quantum dipolar system
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-04 20:00 EDT
Raúl Bombín, Jordi Boronat, Ferran Mazzanti, Juan Sánchez-Baena
Recent experiments have shown that rising the temperature of a dipolar gas under certain conditions leads to a transition to a supersolid state. Here, we employ the path integral Monte Carlo method, which exactly accounts for both thermal and correlation effects, to study that phenomenology in a system of $ ^{162}$ Dy atoms in the canonical ensemble. Our microscopic description allows to quantitatively characterize the emergence of spatial order and superfluidity, the two ingredients that define a supersolid state. Our calculations prove that temperature on its own can promote the formation of a supersolid in a dipolar system. Furthermore, we bridge this exotic phenomenology with the more usual melting of the supersolid at a higher temperature. Our results offer insight into the interplay between thermal excitations, the dipole-dipole interaction, quantum statistics and supersolidity.
Quantum Gases (cond-mat.quant-gas)
4 figures
Topology meets symmetry breaking: Hidden order, intrinsically gapless topological states and finite-temperature topological transitions
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-04 20:00 EDT
Reja H. Wilke, Henning Schlömer, Simon M. Linsel, Annabelle Bohrdt, Fabian Grusdt
Since the discovery of phase transitions driven by topological defects, the classification of phases of matter has been significantly extended beyond Ginzburg and Landau’s paradigm of spontaneous symmetry breaking (SSB). In particular, intrinsic and symmetry-protected topological (SPT) orders have been discovered in (mostly gapped) quantum many-body ground states. However, these are commonly viewed as zero-temperature phenomena, and their robustness in a gapless ground state or against thermal fluctuations remains challenging to tackle. Here we introduce an explicit construction for SPT-type states with hidden order associated with SSB: They feature (quasi) long-range correlations along appropriate edges, but short-range order in the bulk; ground state degeneracy associated with SSB; and non-local string order in the bulk. We apply our construction to predict two types of finite-temperature SPT transitions, in the Ising and BKT class respectively, where the usual signs of criticality appear despite the absence of a diverging correlation length in the bulk. While the state featuring hidden Ising order is gapped, the other SPT state associated with the BKT-SPT transition has hidden $ U(1)$ , or XY-order and constitutes an intrinsically gapless SPT state, associated with a gapless Goldstone mode. Specifically, in this work we discuss spins with global $ \mathbb{Z}_2$ or $ U(1)$ symmetry coupled to link variables constituting a loop gas model. By mapping this system to an Ising-gauge theory, we demonstrate that one of the SPT phases we construct corresponds to the Higgs-SPT phase at $ T=0$ – which we show here to remain stable at finite temperature. Our work paves the way for a more systematic search for hidden order SPT phases, including in gapless systems, and raises the question if a natural (finite-$ T$ ) spin liquid candidate exists that realizes hidden order in the Higgs-SPT class.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
13 pages, 7 figures