CMP Journal 2025-06-25
Statistics
Nature: 24
Physical Review Letters: 12
Review of Modern Physics: 1
arXiv: 48
Nature
Coherent bunching of anyons and dissociation in an interference experiment
Original Paper | Quantum Hall | 2025-06-24 20:00 EDT
Bikash Ghosh, Maria Labendik, Vladimir Umansky, Moty Heiblum, David F. Mross
Aharonov-Bohm interference of fractional quasiparticles in the quantum Hall effect generally reveals their elementary charge (e)1,2,3,4,5,6,7,8,9,10,11,12,13,14,15. Recently, our interferometry experiments with several ‘particle states’ reported flux periods of ΔΦ = (e/e)Φ0 (with Φ0 the flux quantum) at moderate temperatures16. Here we report interference measurements of ‘particle-hole conjugated’ states at filling factors ν = 2/3, 3/5 and 4/7, which revealed unexpected flux periodicities of ΔΦ = ν-1Φ0. The measured shot-noise Fano factor (F) of the partitioned quasiparticles in each of the quantum point contacts of the interferometer was F = ν (ref. 17) rather than that of the elementary charge F = e*/e (refs. 18,19). These observations indicate that the interference of bunched (clustered) elementary quasiparticles occurred for coherent pairs, triples and quadruplets, respectively. A small metallic gate (top gate), deposited in the centre of the interferometer bulk, formed an antidot (or a dot) when charged, thus introducing local quasiparticles at the perimeter of the (anti)dot. Surprisingly, such charging led to a dissociation of the ‘bunched quasiparticles’ and, thus, recovered the conventional flux periodicity set by the elementary charge of the quasiparticles. However, the shot-noise Fano factor (of each quantum point contact) consistently remained at F = ν, possibly due to the neutral modes accompanying the conjugated states. The two observations–bunching and debunching (or dissociation)–were not expected by current theories. Similar effects may arise in Jain’s ‘particle states’ (at lower temperatures) and at even denominator fractional quantum Hall states20.
Quantum Hall, Quantum mechanics
Spin-qubit control with a milli-kelvin CMOS chip
Original Paper | Quantum information | 2025-06-24 20:00 EDT
Samuel K. Bartee, Will Gilbert, Kun Zuo, Kushal Das, Tuomo Tanttu, Chih Hwan Yang, Nard Dumoulin Stuyck, Sebastian J. Pauka, Rocky Y. Su, Wee Han Lim, Santiago Serrano, Christopher C. Escott, Fay E. Hudson, Kohei M. Itoh, Arne Laucht, Andrew S. Dzurak, David J. Reilly
A key virtue of spin qubits is their sub-micron footprint, enabling a single silicon chip to host the millions of qubits required to execute useful quantum algorithms with error correction1,2,3. However, with each physical qubit needing multiple control lines, a fundamental barrier to scale is the extreme density of connections that bridge quantum devices to their external control and readout hardware4,5,6. A promising solution is to co-locate the control system proximal to the qubit platform at milli-kelvin temperatures, wired up by miniaturized interconnects7,8,9,10. Even so, heat and crosstalk from closely integrated control have the potential to degrade qubit performance, particularly for two-qubit entangling gates based on exchange coupling that are sensitive to electrical noise11,12. Here we benchmark silicon metal-oxide-semiconductor (MOS)-style electron spin qubits controlled by heterogeneously integrated cryo-complementary metal-oxide-semiconductor (cryo-CMOS) circuits with a power density sufficiently low to enable scale-up. Demonstrating that cryo-CMOS can efficiently perform universal logic operations for spin qubits, we go on to show that milli-kelvin control has little impact on the performance of single- and two-qubit gates. Given the complexity of our sub-kelvin CMOS platform, with about 100,000 transistors, these results open the prospect of scalable control based on the tight packaging of spin qubits with a ‘chiplet-style’ control architecture.
Quantum information, Qubits
Nerve-to-cancer transfer of mitochondria during cancer metastasis
Original Paper | Breast cancer | 2025-06-24 20:00 EDT
Gregory Hoover, Shila Gilbert, Olivia Curley, Clémence Obellianne, Mike T. Lin, William Hixson, Terry W. Pierce, Joel F. Andrews, Mikhail F. Alexeyev, Yi Ding, Ping Bu, Fariba Behbod, Daniel Medina, Jeffrey T. Chang, Gustavo Ayala, Simon Grelet
The nervous system has a pivotal role in cancer biology, and pathological investigations have linked intratumoural nerve density to metastasis1. However, the precise impact of cancer-associated neurons and the communication channels at the nerve-cancer interface remain poorly understood. Previous cancer denervation models in rodents and humans have highlighted robust cancer dependency on nerves, but the underlying mechanisms that drive nerve-mediated cancer aggressivity remain unknown2,3. Here we show that cancer-associated neurons enhance cancer metabolic plasticity by transferring mitochondria to cancer cells. Breast cancer denervation and nerve-cancer coculture models confirmed that neurons significantly improve tumour energetics. Neurons cocultured with cancer cells undergo metabolic reprogramming, resulting in increased mitochondrial mass and subsequent transfer of mitochondria to adjacent cancer cells. To precisely track the fate of recipient cells, we developed MitoTRACER, a reporter of cell-to-cell mitochondrial transfer that permanently labels recipient cancer cells and their progeny. Lineage tracing and fate mapping of cancer cells acquiring neuronal mitochondria in primary tumours revealed their selective enrichment at metastatic sites following dissemination. Collectively, our data highlight the enhanced metastatic capabilities of cancer cells that receive mitochondria from neurons in primary tumours, shedding new light on how the nervous system supports cancer metabolism and metastatic dissemination.
Breast cancer, Cancer microenvironment, Mechanisms of disease
Evidence for a sub-Jovian planet in the young TWA 7 disk
Original Paper | Exoplanets | 2025-06-24 20:00 EDT
A.-M. Lagrange, C. Wilkinson, M. Mâlin, A. Boccaletti, C. Perrot, L. Matrà, F. Combes, H. Beust, D. Rouan, A. Chomez, J. Milli, B. Charnay, S. Mazevet, O. Flasseur, J. Olofsson, A. Bayo, Q. Kral, A. Carter, K. A. Crotts, P. Delorme, G. Chauvin, P. Thebault, P. Rubini, F. Kiefer, A. Radcliffe, J. Mazoyer, T. Bodrito, S. Stasevic, M. Langlois
Planets are thought to form from dust and gas in protoplanetary disks, with debris disks being the remnants of planet formation. Aged a few million up to a few billion years, debris disks have lost their primordial gas, and their dust is produced by steady-state collisions between larger, rocky bodies1,2. Tens of debris disks, with sizes of tens, sometimes hundreds, of astronomical units have been resolved with high-spatial-resolution, high-contrast imagers at optical and near-infrared or (sub)millimetre interferometers3,4. They commonly show cavities, ring-like structures and gaps, which are often regarded as indirect signatures of the presence of planets that gravitationally interact with unseen planetesimals2,5. However, no planet responsible for these features has been detected yet, probably because of the limited sensitivity (typically 2-10 MJ) of high-contrast imaging instruments (see, for example, refs. 6,7,8,9) before the James Webb Space Telescope. Here we have used the unprecedented sensitivity of the James Webb Space Telescope’s Mid-Infrared Instrument10,11 in the thermal infrared to search for such planets in the disk of the approximately 6.4-Myr-old star TWA 7. With its pole-on orientation, this three-ring debris disk is indeed ideally suited for such a detection. We unambiguously detected a source 1.5 arcsec from the star, which is best interpreted as a cold, sub-Jupiter-mass planet. Its estimated mass (about 0.3 MJ) and position (about 52 au, de-projected) can thoroughly account for the main disk structures.
Exoplanets
Decoding 4-vinylanisole biosynthesis and pivotal enzymes in locusts
Original Paper | Behavioural ecology | 2025-06-24 20:00 EDT
Xiaojiao Guo, Lei Gao, Shiwei Li, Jing Gao, Yuanyuan Wang, Jing Lv, Jiayi Wei, Jing Yang, Han Ke, Qi Ding, Jun Yang, Fusheng Guo, Haowen Zhang, Xiaoguang Lei, Le Kang
Aggregation pheromone, 4-vinylanisole (4VA), is specifically released by gregarious migratory locusts, and is crucial in forming locust swarms that cause destructive plagues1. Control of locust plagues relies heavily on the extensive application of chemical pesticides, which has led to severe environmental and health issues2. As pheromones are primary mediators of insect communication and behaviour3, exploring their biosynthesis can provide important cues to develop innovative behavioural regulators, potentially reducing the reliance on chemical pesticides. Here we resolve the biosynthesis of 4VA and behavioural responses of locusts when enzymes in the 4VA biosynthetic pathway are manipulated. The process initiates with phenylalanine derived from food plants and proceeds through three precursors: cinnamic acid, p-hydroxycinnamic acid and 4-vinylphenol (4VP). Notably, the conversion from 4VP to 4VA through methylation is unique to gregarious locusts. This step is catalysed by two crucial methyltransferases, 4VPMT1 and 4VPMT2. Guided by the X-ray co-crystal structure of 4VPMT2 bound with 4VP and S-adenosyl-l-methionine, we developed 4-nitrophenol as a substrate surrogate. We identified several chemicals that can block 4VA production by inhibiting the enzymatic activities of 4VPMT proteins, thereby suppressing locust aggregative behaviour. The findings uncover the chemical logic behind 4VA biosynthesis and pinpoint two crucial enzymes as novel targets for locust swarm management.
Behavioural ecology, Chemical ecology
A cost-effective all-in-one halide material for all-solid-state batteries
Original Paper | Batteries | 2025-06-24 20:00 EDT
Jiamin Fu, Changhong Wang, Shuo Wang, Joel W. Reid, Jianwen Liang, Jing Luo, Jung Tae Kim, Yang Zhao, Xiaofei Yang, Feipeng Zhao, Weihan Li, Bolin Fu, Xiaoting Lin, Yang Hu, Han Su, Xiaoge Hao, Yingjie Gao, Shutao Zhang, Ziqing Wang, Jue Liu, Hamid Abdolvand, Tsun-Kong Sham, Yifei Mo, Xueliang Sun
All-solid-state batteries require advanced cathode designs to realize their potential for high energy density and economic viability1,2,3. Integrated all-in-one cathodes, which eliminate inactive conductive additives and heterogeneous interfaces, hold promise for substantial energy and stability gains but are hindered by materials lacking sufficient Li+/e- conductivity, mechanical robustness and structural stability4,5,6,7,8,9,10,11,12,13,14. Here we present Li1.3Fe1.2Cl4, a cost-effective halide material that overcomes these challenges. Leveraging reversible Fe2+/Fe3+ redox and rapid Li+/e- transport within its framework, Li1.3Fe1.2Cl4 achieves an electrode energy density of 529.3 Wh kg-1 versus Li+/Li. Critically, Li1.3Fe1.2Cl4 shows unique dynamic properties during cycling, including reversible local Fe migration and a brittle-to-ductile transition that confers self-healing behaviour. This enables exceptional cycling stability, maintaining 90% capacity retention for 3,000 cycles at a rate of 5 C. Integration of Li1.3Fe1.2Cl4 with a nickel-rich layered oxide further increases the energy density to 725.6 Wh kg-1. By harnessing the advantageous dynamic mechanical and diffusion properties of all-in-one halides, this work establishes all-in-one halides as an avenue for energy-dense, durable cathodes in next-generation all-solid-state batteries.
Batteries, Chemical physics
Efficient near-infrared harvesting in perovskite-organic tandem solar cells
Original Paper | Solar cells | 2025-06-24 20:00 EDT
Zhenrong Jia, Xiao Guo, Xinxing Yin, Ming Sun, Jiawei Qiao, Xinyu Jiang, Xi Wang, Yuduan Wang, Zijing Dong, Zhuojie Shi, Chun-Hsiao Kuan, Jingcong Hu, Qilin Zhou, Xiangkun Jia, Jinxi Chen, Zhouyin Wei, Shunchang Liu, Haoming Liang, Nengxu Li, Ling Kai Lee, Renjun Guo, Stephan V. Roth, Peter Müller-Buschbaum, Xiaotao Hao, Xiaoyan Du, Yi Hou
The broad bandgap tunability of both perovskites and organic semiconductors enables the development of perovskite-organic tandem solar cells with promising theoretical efficiency. However, the certified efficiencies of reported perovskite-organic tandem solar cells remain lower than those of single-junction perovskite solar cells, primarily because of insufficient near-infrared photocurrent in narrow-bandgap organic subcells1,2,3. Here we design and synthesize an asymmetric non-fullerene acceptor (NFA), P2EH-1V, featuring a unilateral conjugated π-bridge to reduce the optical bandgap to 1.27 eV while maintaining ideal exciton dissociation and nanomorphology. Transient absorption spectroscopy confirms efficient hole transfer from P2EH-1V to the donor PM6. Devices based on P2EH-1V exhibit reduced non-radiative voltage losses of 0.20 eV without compromising charge-generation efficiency. We achieve a 17.9% efficiency for the organic bottom cell, with a high short-circuit current density (Jsc) of 28.60 mA cm-2. Furthermore, we minimize interface recombination losses, enabling the perovskite top cell to achieve an impressive open-circuit voltage (Voc) of 1.37 V and a fill factor (FF) of 85.5%. These advancements result in perovskite-organic tandem solar cells achieving a record efficiency of 26.7% (certified at 26.4%) over an aperture area greater than 1 cm2.
Solar cells
Rescuing dendritic cell interstitial motility sustains antitumour immunity
Original Paper | Conventional dendritic cells | 2025-06-24 20:00 EDT
Haichao Tang, Zongfang Wei, Bei Zheng, Yumeng Cai, Peihan Wu, Lulu Wu, Xiaohe Ma, Yanqin Chen, Si Su, Jinmin Xu, Yu Qiao, Ying Zhang, Juju Miao, Zijing Yu, Yaodong Zhao, Zhen Xia, Rongjing Zhou, Jian Liu, Jufeng Guo, Zhaoyuan Liu, Qi Xie, Florent Ginhoux, Luming Zhao, Xu Li, Bing Xia, Huanwen Wu, Yongdeng Zhang, Ting Zhou
The dendritic cell (DC)-initiated and sustained cancer immunity cycle is indispensable for effective endogenous and therapeutically mobilized antitumour T cell responses1,2,3,4,5,6,7,8. This necessitates the continuous migration of antigen-carrying DCs from the tumour microenvironment (TME) to the tumour draining lymph nodes (tdLNs)7,8,9,10,11,12,13. Here, through longitudinal analysis of human and mouse tumours, we observed a progressive decrease in migratory conventional DCs (mig-cDCs) in the tdLNs during tumour progression. This decline compromised tumour-specific T cell priming and subsequent T cell supply to the TME. Using a genome-wide in vivo CRISPR screen, we identified phosphodiesterase 5 (PDE5) and its substrate cyclic guanosine monophosphate (cGMP) as key modulators of DC migration. Advanced tumours disrupted cGMP synthesis in DCs to decrease their motility, while PDE5 perturbation preserved the cGMP pool to restore DC migration. Mechanistically, cGMP enhanced myosin-II activity through Rho-associated factors, extending the paradigm of cGMP-regulated amoeboid migration from Dictyostelium to mammalian immune cells. Pharmacological inhibition of PDE5 using sildenafil restored mig-cDC homing to late-stage tdLNs and sustained antitumour immunity in a DC-dependent manner. Our findings bridge fundamental DC interstitial motility to antitumour immunity, revealing that its disruption in chaotic TME promotes immune evasion, and its enhancement offers a promising direction for DC-centric immunotherapy.
Conventional dendritic cells, Tumour immunology
Evidence of Coulomb liquid phase in few-electron droplets
Original Paper | Electronic devices | 2025-06-24 20:00 EDT
Jashwanth Shaju, Elina Pavlovska, Ralfs Suba, Junliang Wang, Seddik Ouacel, Thomas Vasselon, Matteo Aluffi, Lucas Mazzella, Clément Geffroy, Arne Ludwig, Andreas D. Wieck, Matias Urdampilleta, Christopher Bäuerle, Vyacheslavs Kashcheyevs, Hermann Sellier
Emergence of universal collective behaviour from interactions within a sufficiently large group of elementary constituents is a fundamental scientific concept1. In physics, correlations in fluctuating microscopic observables can provide key information about collective states of matter, such as deconfined quark-gluon plasma in heavy-ion collisions2 or expanding quantum degenerate gases3,4. Mesoscopic colliders, through shot-noise measurements, have provided smoking-gun evidence on the nature of exotic electronic excitations such as fractional charges5,6, levitons7 and anyon statistics8. Yet, bridging the gap between two-particle collisions and the emergence of collectivity9 as the number of interacting particles increases10 remains a challenging task at the microscopic level. Here we demonstrate all-body correlations in the partitioning of electron droplets containing up to N = 5 electrons, driven by a moving potential well through a Y-junction in a semiconductor device. Analysing the partitioning data using high-order multivariate cumulants and finite-size scaling towards the thermodynamic limit reveals distinctive fingerprints of a strongly correlated Coulomb liquid. These fingerprints agree well with a universal limit at which the partitioning of a droplet is predicted by a single collective variable. Our electron-droplet scattering experiments illustrate how coordinated behaviour emerges through interactions of only a few elementary constituents. Studying similar signatures in other physical platforms such as cold-atom simulators4,11 or collections of anyonic excitations8,12 may help identify emergence of exotic phases and, more broadly, advance understanding of matter engineering.
Electronic devices, Particle physics, Phase transitions and critical phenomena, Quantum dots
An aspirational approach to planetary futures
Review Paper | Developing world | 2025-06-24 20:00 EDT
Erle C. Ellis, Yadvinder Malhi, Hannah Ritchie, Jasper Montana, Sandra Díaz, David Obura, Susan Clayton, Melissa Leach, Laura Pereira, Emma Marris, Michael Muthukrishna, Bojie Fu, Peter Frankopan, Molly K. Grace, Samira Barzin, Krushil Watene, Nicholas Depsky, Josefin Pasanen, Pedro Conceição
Prevailing frameworks to address planetary environmental challenges tend to focus on setting goals, targets, or boundaries to limit human harm to ecosystems or species. Here we propose an aspirational approach aimed at empowering people to shape a better future for all of life on Earth. We do this by building on the human development approach and its supporting metrics, especially the Human Development Index (HDI), a broadly influential framework that has contributed to decades of human progress by measuring and promoting people’s capabilities to lead the lives that they value. Rather than assessing the state or dynamics of the biosphere, we propose the Nature Relationship Index (NRI), which would focus on measuring the progress of nations towards delivering mutually beneficial relationships among people and the rest of the living world in terms that people widely understand and value. Through an open-ended process informed by expert consultation, international concept testing and indicator development, the NRI could help to incentivize progress towards a world in which humanity thrives together with the rest of life on Earth. We explore the challenges and opportunities of developing a robust NRI and invite broader participation to facilitate this development in collaboration with the United Nations Development Programme Human Development Report.
Developing world, Geography, Sustainability
RNA codon expansion via programmable pseudouridine editing and decoding
Original Paper | Chemical modification | 2025-06-24 20:00 EDT
Jiangle Liu, Xueqing Yan, Hao Wu, Ziqin Ji, Ye Shan, Xinyan Wang, Yunfan Ran, Yichen Ma, Caitao Li, Yuchao Zhu, Ruichu Gu, Han Wen, Chengqi Yi, Peng R. Chen
The incorporation of non-canonical amino acids (ncAAs) enables customized chemistry to tailor protein functions1,2,3. Genetic code expansion offers a general approach for ncAA encoding by reassigning stop codons as the ‘blank’ codon; however, it is not completely orthogonal to translation termination for cellular transcripts. Here, to generate more bona fide blank codons, we developed an RNA codon-expansion (RCE) strategy that introduces and decodes bioorthogonally assignable pseudouridine (Ψ) codons (ΨGA, ΨAA or ΨAG) on specified mRNA transcripts to incorporate ncAAs in mammalian cells. The RCE strategy comprises a programmable guide RNA4, an engineered decoder tRNA, and aminoacyl-tRNA synthetase. We first developed the RCE(ΨGA) system, which incorporates functional ncAAs into proteins via the ΨGA codon, demonstrating a higher translatome-wide and proteomic specificity compared with the genetic code expansion system. We further expanded our strategy to produce the RCE(ΨAA) and RCE(ΨAG) systems, with all three Ψ codon:(Ψ codon)-tRNAPyl pairs exhibiting mutual orthogonality. Moreover, we demonstrated that the RCE system cooperates compatibly with the genetic code expansion strategy for dual ncAA encoding. In sum, the RCE method utilized Ψ as a post-transcriptional ‘letter’ to encode and decode RNA codons in specific mRNA transcripts, opening a new route for genetic alphabet expansion and site-specific ncAA incorporation in eukaryotic cells.
Chemical modification, RNA
Interactions between TTYH2 and APOE facilitate endosomal lipid transfer
Original Paper | Cryoelectron microscopy | 2025-06-24 20:00 EDT
Anastasiia Sukalskaia, Andreas Karner, Anna Pugnetti, Florian Weber, Birgit Plochberger, Raimund Dutzler
The Tweety homologues (TTYHs) constitute a family of eukaryotic membrane proteins that, on the basis of structural features, were recently proposed to contribute to lipid transfer between soluble carriers and cellular membranes1. However, in the absence of supporting data, this function was hypothetical. Here through pull-down of endogenous proteins, we identify APOE as the interaction partner of human TTYH2. Subcellular fractionation and immunocytochemistry assays showed that both proteins colocalize in endosomal compartments. Characterization of the specific interaction between APOE and TTYH2 through binding assays and structural studies enabled us to identify an epitope in an extended domain of TTYH2 that faces the endosomal lumen. Structures of complexes with APOE-containing lipoprotein particles revealed a binding mode that places lipids in a suitable position to facilitate their diffusion into the membrane. Moreover, in vitro studies revealed that lipid transfer is accelerated by TTYH2. Collectively, our findings indicate that TTYH2 has a role in the unloading of APOE-containing lipoproteins after they are endocytosed. These results define a new protein class that facilitates the extraction of lipids from and their insertion into cellular membranes. Although ubiquitous, this process could be of particular relevance in the brain, where APOE is involved in the transfer of lipids between astrocytes and neurons.
Cryoelectron microscopy, Membrane biophysics, Permeation and transport
Spatiotemporal orchestration of mitosis by cyclin-dependent kinase
Original Paper | Cell division | 2025-06-24 20:00 EDT
Nitin Kapadia, Paul Nurse
Mitotic onset is a critical transition for eukaryotic cell proliferation. The commonly held view of mitotic control is that the master regulator, cyclin-dependent kinase (CDK), is first activated in the cytoplasm, at the centrosome, initiating mitosis1,2,3. Bistability in CDK activation ensures that the transition is irreversible, but how this unfolds in a spatially compartmentalized cell is unknown4,5,6,7,8. Here, using fission yeast, we show that CDK is first activated in the nucleus, and that the bistable responses differ markedly between the nucleus and the cytoplasm, with a stronger response in the nucleus driving mitotic signal propagation from there to the cytoplasm. Abolishing cyclin-CDK localization to the centrosome led to activation occurring only in the nucleus, spatially uncoupling the nucleus and cytoplasm mitotically, suggesting that centrosomal cyclin-CDK acts as a ‘signal relayer’. We propose that the key mitotic regulatory system operates in the nucleus in proximity to DNA, which enables incomplete DNA replication and DNA damage to be effectively monitored to preserve genome integrity and to integrate ploidy within the CDK control network. This spatiotemporal regulatory framework establishes core principles for control of the onset of mitosis and highlights that the CDK control system operates within distinct regulatory domains in the nucleus and cytoplasm.
Cell division, Mitosis, Multistability, Oscillators, Single-cell imaging
Controlling diverse robots by inferring Jacobian fields with deep networks
Original Paper | Computer science | 2025-06-24 20:00 EDT
Sizhe Lester Li, Annan Zhang, Boyuan Chen, Hanna Matusik, Chao Liu, Daniela Rus, Vincent Sitzmann
Mirroring the complex structures and diverse functions of natural organisms is a long-standing challenge in robotics1,2,3,4. Modern fabrication techniques have greatly expanded the feasible hardware5,6,7,8, but using these systems requires control software to translate the desired motions into actuator commands. Conventional robots can easily be modelled as rigid links connected by joints, but it remains an open challenge to model and control biologically inspired robots that are often soft or made of several materials, lack sensing capabilities and may change their material properties with use9,10,11,12. Here, we introduce a method that uses deep neural networks to map a video stream of a robot to its visuomotor Jacobian field (the sensitivity of all 3D points to the robot’s actuators). Our method enables the control of robots from only a single camera, makes no assumptions about the robots’ materials, actuation or sensing, and is trained without expert intervention by observing the execution of random commands. We demonstrate our method on a diverse set of robot manipulators that vary in actuation, materials, fabrication and cost. Our approach achieves accurate closed-loop control and recovers the causal dynamic structure of each robot. Because it enables robot control using a generic camera as the only sensor, we anticipate that our work will broaden the design space of robotic systems and serve as a starting point for lowering the barrier to robotic automation.
Computer science, Electrical and electronic engineering, Mechanical engineering
Engrafted nitrergic neurons derived from hPSCs improve gut dysmotility in mice
Original Paper | Differentiation | 2025-06-24 20:00 EDT
Homa Majd, Ryan M. Samuel, Andrius Cesiulis, Jonathan T. Ramirez, Ali Kalantari, Kevin Barber, Sina Farahvashi, Zaniar Ghazizadeh, Alireza Majd, Angeline K. Chemel, Mikayla N. Richter, Subhamoy Das, Jacqueline L. Bendrick, Matthew G. Keefe, Jeffrey Wang, Rahul K. Shiv, Samyukta Bhat, Matvei Khoroshkin, Johnny Yu, Tomasz J. Nowakowski, Kwun Wah Wen, Hani Goodarzi, Nikhil Thapar, Julia A. Kaltschmidt, Conor J. McCann, Faranak Fattahi
Gastrointestinal (GI) motility disorders represent a major medical challenge, with few effective therapies available. These disorders often result from dysfunction of inhibitory nitric oxide (NO)-producing motor neurons in the enteric nervous system, which are essential for regulating gut motility. Loss or dysfunction of NO neurons is linked to severe conditions, including achalasia, gastroparesis, intestinal pseudo-obstruction and chronic constipation1,2. Here we introduce a platform based on human pluripotent stem cells (hPSCs) for therapeutic development targeting GI motility disorders. Using an unbiased screen, we identified drug candidates that modulate NO neuron activity and enhance motility in mouse colonic tissue ex vivo. We established a high-throughput strategy to define developmental programs driving the specification of NO neurons and found that inhibition of platelet-derived growth factor receptors (PDGFRs) promotes their differentiation from precursors of the enteric nervous system. Transplantation of these neurons into NO-neuron-deficient mice led to robust engraftment and improved GI motility, offering a promising cell-based therapy for neurodegenerative GI disorders. These studies provide a new framework for understanding and treating enteric neuropathies.
Differentiation, Regeneration, Regeneration and repair in the nervous system, Stem-cell differentiation
The expanding repertoire of ESCRT functions in cell biology and disease
Review Paper | Endosomes | 2025-06-24 20:00 EDT
James H. Hurley, Alyssa N. Coyne, Marta Miączyńska, Harald Stenmark
The endosomal sorting complex required for transport (ESCRT) is a multicomplex machinery comprising proteins that are conserved from bacteria to humans and has diverse roles in regulating the dynamics of cellular membranes. ESCRT functions have far-reaching consequences for cell biological processes such as intracellular traffic, membrane repair, cell signalling, metabolic regulation, cell division and genome maintenance. Here we review recent insights that emphasize the pathophysiological consequences of ESCRT dysfunctions, including infections, immune disorders, cancers and neurological diseases. We highlight the possibilities of using our knowledge about ESCRT structures and functions for drug discovery.
Endosomes, ESCRT, Mechanisms of disease
Barcoded viral tracing identifies immunosuppressive astrocyte-glioma interactions
Original Paper | Immune evasion | 2025-06-24 20:00 EDT
Brian M. Andersen, Camilo Faust Akl, Michael A. Wheeler, Zhaorong Li, Martin Diebold, Michael Kilian, Joseph M. Rone, Aditya Misra, Jessica E. Kenison, Joon-Hyuk Lee, Hong-Gyun Lee, Carolina M. Polonio, David Merrell, Jakob H. Weiss, Lillie Godinez, Gavin Piester, Tomer Illouz, Jessica J. Ye, Arianna Ghia, Jazmin Martinez, Elizabeth N. Chung, Lena Srun, Daniel Farrenkopf, Lucas E. Flausino, Anton M. Schüle, Liliana M. Sanmarco, Federico Giovannoni, Luca Fehrenbacher, Marc Charabati, Cristina Gutiérrez-Vázquez, Margaret M. Cusick, Prem S. Prabhakar, Connor C. Bossi, Emily Lapinskas, Roni Nowarski, Gad Getz, Keith L. Ligon, Marco Prinz, E. Antonio Chiocca, David A. Reardon, Francisco J. Quintana
Glioblastoma (GBM) is the most lethal primary brain malignancy1. Immunosuppression in the GBM tumour microenvironment (TME) is an important barrier to immune-targeted therapies, but our understanding of the mechanisms of immune regulation in the GBM TME is limited2. Here we describe a viral barcode interaction-tracing approach3 to analyse TME cell-cell communication in GBM clinical samples and preclinical models at single-cell resolution. We combine it with single-cell and bulk RNA-sequencing analyses, human organotypic GBM cultures, in vivo cell-specific CRISPR-Cas9-driven genetic perturbations as well as human and mouse experimental systems to identify an annexin A1-formyl peptide receptor 1 (ANXA1-FPR1) bidirectional astrocyte-GBM communication pathway that limits tumour-specific immunity. FPR1 inhibits immunogenic necroptosis in tumour cells, and ANXA1 suppresses NF-κB and inflammasome activation in astrocytes. ANXA1 expression in astrocytes and FPR1 expression in cancer cells are associated with poor outcomes in individuals with GBM. The inactivation of astrocyte-glioma ANXA1-FPR1 signalling enhanced dendritic cell, T cell and macrophage responses, increasing infiltration by tumour-specific CD8+ T cells and limiting T cell exhaustion. In summary, we have developed a method to analyse TME cell-cell interactions at single-cell resolution in clinical samples and preclinical models, and used it to identify bidirectional astrocyte-GBM communication through ANXA1-FPR1 as a driver of immune evasion and tumour progression.
Immune evasion, Tumour immunology
The dynamics and geometry of choice in the premotor cortex
Original Paper | Decision | 2025-06-24 20:00 EDT
Mikhail Genkin, Krishna V. Shenoy, Chandramouli Chandrasekaran, Tatiana A. Engel
The brain represents sensory variables in the coordinated activity of neural populations, in which tuning curves of single neurons define the geometry of the population code1,2. Whether the same coding principle holds for dynamic cognitive variables remains unknown because internal cognitive processes unfold with a unique time course on single trials observed only in the irregular spiking of heterogeneous neural populations3,4,5,6,7,8. Here we show the existence of such a population code for the dynamics of choice formation in the primate premotor cortex. We developed an approach to simultaneously infer population dynamics and tuning functions of single neurons to the population state. Applied to spike data recorded during decision-making, our model revealed that populations of neurons encoded the same dynamic variable predicting choices, and heterogeneous firing rates resulted from the diverse tuning of single neurons to this decision variable. The inferred dynamics indicated an attractor mechanism for decision computation. Our results reveal a unifying geometric principle for neural encoding of sensory and dynamic cognitive variables.
Decision, Dynamical systems, Network models, Neural encoding
In-line NMR guided orthogonal transformation of real-life plastics
Original Paper | Chemical engineering | 2025-06-24 20:00 EDT
Mei-Qi Zhang, Yida Zhou, Ruochen Cao, Shuheng Tian, Yuchen Jiao, Zhenbo Guo, Maolin Wang, Hongpeng Peng, Bo Sun, Bingjun Xu, Meng Wang, Shutao Xu, Ding Ma
The global crisis of plastic waste accumulation threatens wildlife and ecosystems1. Catalytic processes that convert plastic waste into valuable chemicals and fuels offer promising solutions2. Recycling or upcycling of real-life plastic mixtures is challenging owing to their diverse composition and structure3. Here we propose a product-oriented strategy leveraging the orthogonality in reactivities of different functional groups in plastic mixtures to yield valuable products. This approach involves identifying functional groups followed by converting a selective component in the mixture to valuable products. We use mixtures of polystyrene, polylactic acid, polyurethane, polycarbonate, polyvinyl chloride, polyethylene terephthalate, polyethylene and polypropylene, as well as real-life plastics, to demonstrate the feasibility and effectiveness of the proposed strategy. The diverse physical and chemical properties of these components, which typically hinder direct recovery, offer opportunities for extraction and transformation with the proposed strategy. From a 20-g mixture of real-life plastics, including polystyrene foam, a polylactic acid straw, a polyurethane tube, a polycarbonate mask, a polyvinyl chloride bag, a polyethylene terephthalate bottle, a polyethylene dropper and a polypropylene bottle, we obtained more than 8 separate chemicals: 1.3 g of benzoic acid, 0.5 g of plasticizer, 0.7 g of alanine, 0.7 g of lactic acid, 1.4 g of aromatic amine salt, 2.1 g of bisphenol A, 2.0 g of terephthalic acid and 3.5 g of C3-C6 alkanes. This study reveals the potential for designing transformation strategies for complex plastic waste based on their chemical nature and opens paths for managing end-of-life plastic mixtures.
Chemical engineering, Polymer chemistry, Polymers
Mechanism of cytarabine-induced neurotoxicity
Original Paper | Cancer | 2025-06-24 20:00 EDT
Jia-Cheng Liu, Dongpeng Wang, Elsa Callen, Chuanyuan Chen, Santiago Noriega, Yafang Shang, David Schürmann, Yawei Song, Gokul N. Ramadoss, Raj Chari, Nancy Wong, Yongge Zhao, Yuan He, Peter D. Aplan, Michael E. Ward, Nathaniel Heintz, Anjana Rao, Peter J. McKinnon, Keith W. Caldecott, Primo Schär, Fei-Long Meng, Ferenc Livak, Wei Wu, André Nussenzweig
Postmitotic neurons have high levels of methylated cytosine and its oxidized intermediates such as 5-hydroxymethylcytosine1. However, the functional relevance of these epigenetic modifications of DNA are poorly understood. Here we show that some cytidine analogues, such as cytarabine, cause DNA double-strand breaks during TET-mediated active 5-methylcytosine demethylation by interrupting TDG-dependent base excision repair. These double-strand breaks are frequently converted into deletions and translocations by DNA ligase 4. In vivo, Purkinje and Golgi cells in the cerebellum are the only neuronal populations that exhibit high levels of DNA damage due to cytarabine. In Purkinje cells, TET targets highly expressed gene bodies marked by enhancer-associated histone modifications. Many of these genes control movement coordination, which explains the long-recognized cerebellar neurotoxicity of cytarabine2. We show that other cytidine analogues, such as gemcitabine, cause only single-strand breaks in neurons, which are repaired by DNA ligase 3 with minimal toxicity. Our findings uncover a mechanistic link between TET-mediated DNA demethylation, base excision repair and gene expression in neurons. The results also provide a rational explanation for the different neurotoxicity profiles of an important class of antineoplastic agents.
Cancer, Neuroscience
A cation-exchange approach to tunable magnetic intercalation superlattices
Original Paper | Magnetic properties and materials | 2025-06-24 20:00 EDT
Jingxuan Zhou, Jingyuan Zhou, Zhong Wan, Qi Qian, Huaying Ren, Xingxu Yan, Boxuan Zhou, Ao Zhang, Xiaoqing Pan, Wuzhang Fang, Yuan Ping, Zdenek Sofer, Yu Huang, Xiangfeng Duan
Tailoring magnetic ordering in solid-state materials is essential for emerging spintronics1,2. However, substitutional lattice doping in magnetic semiconductors is often constrained by the low solubility of magnetic elements3,4,5, limiting the maximum achievable doping concentration (for example, less than 5%) and ferromagnetic ordering temperature6. The intercalation of magnetic elements in layered two-dimensional atomic crystals (2DACs) without breaking in-plane covalent bonds offers an alternative approach to incorporate a much higher concentration of magnetic atoms (for example, up to 50%) beyond the typical solubility limit. However, commonly used chemical and electrochemical intercalation methods are largely confined to a few isolated examples so far. Here we report a general two-step intercalation and cation-exchange strategy to produce a library of highly ordered magnetic intercalation superlattices (MISLs) with tunable magnetic ordering. Monovalent transition-metal cations Cu+ and Ag+, divalent magnetic cations Mn2+, Fe2+, Co2+ and Ni2+, and trivalent rare-earth cations Eu3+ and Gd3+ have been successfully incorporated into group-VIB 2DACs, including MoS2, MoSe2, MoTe2, WS2, WSe2 and WTe2, and group-IVB, -VB, -IIIA, -IVA and -VA 2DACs, including TiS2, NbS2, NbSe2, TaS2, In2Se3, SnSe2, Bi2Se3 and Bi2Te3. We show that these MISLs can be prepared with tunable concentrations of magnetic intercalants, enabling tailored magnetic ordering across a diverse array of functional 2DACs, including semiconductors, topological insulators, and superconductors. This work establishes a versatile material platform for both fundamental investigations and spintronics applications.
Magnetic properties and materials, Synthesis and processing, Two-dimensional materials
Soft magnetic hysteresis in a dysprosium amide-alkene complex up to 100 kelvin
Original Paper | Inorganic chemistry | 2025-06-24 20:00 EDT
Jack Emerson-King, Gemma K. Gransbury, Benjamin E. Atkinson, William J. A. Blackmore, George F. S. Whitehead, Nicholas F. Chilton, David P. Mills
Lanthanides have shown magnetic memory at both the atomic1,2 and molecular3,4 level. The magnetic remanence temperatures of lanthanide single-molecule magnets can surpass d-transition metal examples5,6, and since 2017, energy barriers to magnetic reversal (Ueff) from 1,237(28) cm-1 to 1,631(25) cm-1 and open magnetic hysteresis loops between 40 K and 80 K have typically been achieved with axial dysprosium(III) bis(cyclopentadienyl) complexes7,8,9,10,11,12,13,14,15,16,17. It has been predicted that linear dysprosium(III) compounds could deliver greater mJ (the projection of the total angular momentum, J, on a quantization axis labelled z) state splitting and therefore higher Ueff and hysteresis temperatures18,19,20,21, but as lanthanide bonding is predominantly ionic22,23, so far dysprosium bis(amide) complexes have shown highly bent geometries that promote fast magnetic reversal24,25. Here we report a dysprosium bis(amide)-alkene complex, [Dy{N(SiiPr3)[Si(iPr)2C(CH3)=CHCH3]}{N(SiiPr3)(SiiPr2Et)}][Al{OC(CF3)3}4] (1-Dy), that shows Ueff = 1,843(11) cm-1 and slow closing of soft magnetic hysteresis loops up to 100 K. Calculations show that the Ueff value for 1-Dy arises from the charge-dense amide ligands, with a pendant alkene taking a structural role to enforce a large N-Dy-N angle while imposing only a weak equatorial interaction. This leads to molecular spin dynamics up to 100 times slower than the current best single-molecule magnets above 90 K.
Inorganic chemistry, Magnetic properties and materials, Organometallic chemistry
Computer-vision research powers surveillance technology
Original Paper | Computer science | 2025-06-24 20:00 EDT
Pratyusha Ria Kalluri, William Agnew, Myra Cheng, Kentrell Owens, Luca Soldaini, Abeba Birhane
An increasing number of scholars, policymakers and grassroots communities argue that artificial intelligence (AI) research–and computer-vision research in particular–has become the primary source for developing and powering mass surveillance1,2,3,4,5,6,7. Yet, the pathways from computer vision to surveillance continue to be contentious. Here we present an empirical account of the nature and extent of the surveillance AI pipeline, showing extensive evidence of the close relationship between the field of computer vision and surveillance. Through an analysis of computer-vision research papers and citing patents, we found that most of these documents enable the targeting of human bodies and body parts. Comparing the 1990s to the 2010s, we observed a fivefold increase in the number of these computer-vision papers linked to downstream surveillance-enabling patents. Additionally, our findings challenge the notion that only a few rogue entities enable surveillance. Rather, we found that the normalization of targeting humans permeates the field. This normalization is especially striking given patterns of obfuscation. We reveal obfuscating language that allows documents to avoid direct mention of targeting humans, for example, by normalizing the referring to of humans as ‘objects’ to be studied without special consideration. Our results indicate the extensive ties between computer-vision research and surveillance.
Computer science, Publishing
Broadband transient full-Stokes luminescence spectroscopy
Original Paper | Circular dichroism | 2025-06-24 20:00 EDT
Antti-Pekka M. Reponen, Marcel Mattes, Zachary A. VanOrman, Lilian Estaque, Grégory Pieters, Sascha Feldmann
Materials emitting circularly polarized light (CPL) are highly sought after for applications ranging from efficient displays to quantum information technologies1,2,3,4,5,6,7. However, established methods for time-resolved CPL (TRCPL) characterization have notable limitations8,9,10,11,12,13,14,15,16,17, generally requiring a compromise between sensitivity, accessible timescales and spectral information. This has limited the acquisition of in-depth photophysical insight necessary for materials development. Here we demonstrate a high-sensitivity (noise level of the order of 10-4), broadband (about 400-900 nm), transient (nanosecond resolution, millisecond range) full-Stokes (CPL and linear polarizations) spectroscopy setup. The achieved combination of high-sensitivity, broad wavelength response and flexible time ranges represents a substantial advancement over previous TRCPL approaches. As a result, TRCPL measurements are shown to be applicable to hitherto inaccessible material systems and photophysical processes, including systems with low (10-3) dissymmetry factors and luminescence pathways spanning nanosecond to millisecond time ranges. Finally, full-Stokes measurements allow tracking the temporal evolution of linear polarization components, of interest by themselves, but especially relevant in the context of controlling for associated CPL artefacts18,19 in the time domain.
Circular dichroism, Optical spectroscopy, Techniques and instrumentation
Physical Review Letters
First Search for Ultralight Dark Matter Using a Magnetically Levitated Particle
Research article | Optomechanics | 2025-06-24 06:00 EDT
Dorian W. P. Amaral, Dennis G. Uitenbroek, Tjerk H. Oosterkamp, and Christopher D. Tunnell
We perform the first search for ultralight dark matter using a magnetically levitated particle. A submillimeter permanent magnet is levitated in a superconducting trap with a measured force sensitivity of $0.2\text{ }\text{ }\mathrm{fN}/\sqrt{\mathrm{Hz}}$. We find no evidence of a signal and derive limits on dark matter coupled to the difference between baryon and lepton number, $B- L$, in the mass range $(1.10360- 1.10485)\times{}{10}^{- 13}\text{ }\text{ }\mathrm{eV}/{c}^{2}$. Our most stringent limit on the coupling strength is ${g}_{B- L}\lesssim 2.98\times{}{10}^{- 21}$. We propose the POLONAISE (Probing Oscillations using Levitated Objects for Novel Accelerometry In Searches of Exotic physics) experiment, which features short-, medium-, and long-term upgrades that will give us leading sensitivity in a wide mass range, demonstrating the promise of this novel quantum sensing technology in the hunt for dark matter.
Phys. Rev. Lett. 134, 251001 (2025)
Optomechanics, Phenomenology, Quantum measurements, Dark matter detectors, Magnetic levitation
Sullivan Process near Threshold and the Pion Gravitational Form Factors
Research article | Form factors | 2025-06-24 06:00 EDT
Yoshitaka Hatta and Jakob Schoenleber
We propose a novel method to experimentally access the gravitational form factors of the charged pion ${\pi }^{+}$ through the Sullivan process in electron-proton scattering. We demonstrate that the cross sections of $J/\psi $ photoproduction and $\phi $ electroproduction near the respective thresholds are dominated by the gluon gravitational form factor of the pion to next-to-leading order in perturbative QCD. We predict cross sections for the Electron-Ion Collider and the Jefferson Lab experiments.
Phys. Rev. Lett. 134, 251901 (2025)
Form factors, Generalized parton distributions, Quantum chromodynamics
Lattice-QCD Computable Quark Correlation Functions at Three-Loop Order and Extraction of Splitting Functions
Research article | Lattice QCD | 2025-06-24 06:00 EDT
Chen Cheng, Li-Hong Huang, Xiang Li, Zheng-Yang Li, and Yan-Qing Ma
We present the first complete next-to-next-to-next-to-leading-order calculation of the matching coefficients that link unpolarized flavor nonsinglet parton distribution functions with lattice QCD computable correlation functions. By using this high-order result, we notice a reduction in theoretical uncertainties compared to relying solely on previously known lower-order matching coefficients. Furthermore, based on this result we have extracted the three-loop unpolarized flavor nonsinglet splitting function, which is in agreement with the state-of-the-art result. Because of the simplicity of our method, it has the potential to advance the calculation of splitting functions to the desired four-loop order.
Phys. Rev. Lett. 134, 251902 (2025)
Lattice QCD, Parton distribution functions, Perturbative QCD, Strong interaction
Energy-Energy Correlator for Jet Production in $pp$ and $pA$ Collisions
Research article | Perturbative QCD | 2025-06-24 06:00 EDT
João Barata, Zhong-Bo Kang, Xoán Mayo López, and Jani Penttala
In this Letter, we study the collinear limit of the energy-energy correlator in single-inclusive jet production in proton-proton and proton-nucleus collisions. We introduce a nonperturbative model that allows us to describe the energy-energy correlator in the entire angular region of the current experiments. Our results for proton-proton collisions show excellent agreement with CMS and ALICE data over a wide range of jet transverse momenta. For proton-nucleus collisions, we include modifications from the nuclear medium, and our predictions align well with the trends observed in recent ALICE measurements.
Phys. Rev. Lett. 134, 251903 (2025)
Perturbative QCD, QCD phenomenology, Strong interaction
Photoelectron Circular Dichroism of a Chiral Molecule Induced by Resonant Interatomic Coulombic Decay from an Antenna Atom
Research article | Atomic & molecular clusters | 2025-06-24 06:00 EDT
Stefan Yoshi Buhmann, Andreas Hans, Janine C. Franz, and Philipp V. Demekhin
We show that a nonchiral atom can act as an antenna to induce a photoelectron circular dichroism in a nearby chiral molecule in a three-step process: The donor atom (antenna) is initially resonantly excited by circularly polarized radiation. It then transfers its excess energy to the acceptor molecule by means of resonant interatomic Coulombic decay. The latter finally absorbs the energy and emits an electron that exhibits the aforementioned circular dichroism in its angular distribution. We study the process on the basis of the retarded dipole–dipole interaction and report an asymptotic analytic expression for the distance-dependent chiral asymmetry of the photoelectron as induced by resonant interatomic Coulombic decay for random line-of-sight and acceptor orientations. In the nonretarded limit, the predicted chiral asymmetry is reversed as compared to that of a direct photoelectron circular dichroism of the molecule.
Phys. Rev. Lett. 134, 253001 (2025)
Atomic & molecular clusters, Autoionization & Auger processes, Electronic excitation & ionization, Electronic structure of atoms & molecules, Photoemission
Vortex to Rotons Transition in Dipolar Bose-Einstein Condensates
Research article | Bose-Einstein condensates | 2025-06-24 06:00 EDT
Alberto Villois, Miguel Onorato, and Davide Proment
Dipolar Bose-Einstein condensates (dBECs) exhibit a plethora of physics phenomena, from supersolidity to the rotonlike minimum in the elementary excitation spectrum. In this work we first demonstrate the existence of axis-symmetric solitary waves in (quasi-)two-dimensional dBECs: these localized excitations are characterized by quantized vortex dipoles that continuously transit to vortex-free density depletions. We then show how the presence of the roton minimum fundamentally alters the fate of such solutions when approaching Landau’s critical speed: when propagating along the polarization direction where the roton minimum occurs, the solitary wave transits into roton excitations rather than into phonons as for standard contact-interaction BECs. This finding suggests that Feynman’s hypothesis, conjectured for 3D superfluid liquid helium regarding the creation of rotons as fading vortex excitations, is valid in the context of 2D dBECs.
Phys. Rev. Lett. 134, 253401 (2025)
Bose-Einstein condensates, Dipolar gases, Vortices in superfluids, Quantum fluids & solids, Solitons
Stabilizing an Ultracold Fermi Gas against Fermi Acceleration to Superdiffusion through Localization
Research article | Anderson localization | 2025-06-24 06:00 EDT
S. Barbosa, M. Kiefer-Emmanouilidis, F. Lang, J. Koch, and A. Widera
Anderson localization, i.e., destructive quantum interference of multiple-scattering paths, halts transport entirely. Contrarily, time-dependent random forces expedite transport via Fermi acceleration, proposed as a mechanism for high-energy cosmic rays. Their competition creates interesting dynamics, but experimental observations are scarce. Here, we experimentally study the expansion of an ultracold Fermi gas inside time-dependent disorder and observe distinct regimes from sub- to superdiffusion. Unexpectedly, quantum interference counteracts acceleration in strong disorder before a transition to a diffusive state occurs in the driven system. Our system enables the investigation of Fermi acceleration in the quantum-transport regime.
Phys. Rev. Lett. 134, 253402 (2025)
Anderson localization, Anomalous diffusion, Cold atoms & matter waves, Weak localization, Disordered systems, Fermi gases, Nonequilibrium systems
Theory of Internal Conversion of the $^{229}\mathrm{Th}$ Nuclear Isomer in Solid-State Hosts
Research article | Atomic, optical & lattice clocks | 2025-06-24 06:00 EDT
H. W. T. Morgan, H. B. Tran Tan, R. Elwell, A. N. Alexandrova, Eric R. Hudson, and Andrei Derevianko
Ab initio relativistic treatment of electron-nuclear interaction provides crucial physical understanding for the development of solid-state nuclear clocks.
Phys. Rev. Lett. 134, 253801 (2025)
Atomic, optical & lattice clocks, Density functional theory, Nuclear transition rates
Universal Exchange-Correlation Surface Asymptotics: Metal Slabs Versus Semi-infinite Metal Surfaces
Research article | Approximation methods for many-body systems | 2025-06-24 06:00 EDT
C. M. Horowitz, C. R. Proetto, and J. M. Pitarke
Density-functional theory is well known to rely on approximations to the unknown exchange-correlation ($xc$) energy functional, which can be constructed from the satisfaction of a number of known properties. One of those properties is the asymptotic behavior of exchange and correlation in localized or extended many-electron systems. However, the actual asymptotics of the $xc$ energy and potential in the vacuum region of a metal surface have remained elusive over the years. Here, we report what we consider to be a final word for the asymptotics of the $xc$ energy per particle ${\epsilon}{xc}n$ and the $xc$ Kohn-Sham potential ${v}{xc}n$ in the vacuum side of both an extended semi-infinite metal and a localized metal slab, which are always universal (i.e., electron-density independent), negative, and inversely proportional to the distance from the surface. We find that, contrary to previous conclusions by other authors, while for extended systems the asymptotics are dominated by a type of correlation, for metal slabs they are dominated by exchange, as in the case of systems that are finite in all directions, like atoms, molecules, and metal clusters.
Phys. Rev. Lett. 134, 256401 (2025)
Approximation methods for many-body systems, Density functional theory, First-principles calculations
Accurate Simulation of the Hubbard Model with Finite Fermionic Projected Entangled Pair States
Research article | Quantum simulation | 2025-06-24 06:00 EDT
Wen-Yuan Liu, Huanchen Zhai, Ruojing Peng, Zheng-Cheng Gu, and Garnet Kin-Lic Chan
Simulations of the 2D Hubbard model by tensor networks surpass the accuracy and simulation sizes accessible to Density Matrix Renormalization Group.
Phys. Rev. Lett. 134, 256502 (2025)
Quantum simulation, Hubbard model, Projected entangled pair states, Tensor network methods, Tensor network renormalization
Inverse Melting of Polar Order in Chemically Substituted ${\mathrm{BaTiO}}_{3}$
Research article | Crystal melting | 2025-06-24 06:00 EDT
Yang Zhang, Suk Hyun Sung, Colin B. Clement, Sang-Wook Cheong, and Ismail El Baggari
In many condensed matter systems, long-range order emerges at low temperatures as thermal fluctuations subside. In the presence of competing interactions or quenched disorder, however, some systems can show unusual configurations that become more disordered at low temperature, a rare phenomenon known as ‘’inverse melting.’’ Here, we discover an inverse melting of the polar order in a ferroelectric oxide with quenched chemical disorder (${\mathrm{BaTi}}{1- x}{\text{Zr}}{x}{\mathrm{O}}{3}$) through direct atomic-scale visualization using in situ scanning transmission electron microscopy. In contrast to the clean ${\mathrm{BaTiO}}{3}$ parent system in which long-range order tracks lower temperatures, we observe in the doped system ${\mathrm{BaTi}}{1- x}{\text{Zr}}{x}{\mathrm{O}}_{3}$ that thermally driven fluctuations at high temperature give way to a more ordered state and then to a reentrant disordered configuration at even lower temperature. Such an inverse melting of the polar order is likely linked to the random field generated by Zr dopants, which modulates the energy landscape arising from the competition between thermal fluctuations and random field pinning potential. These visualizations highlight a rich landscape of order and disorder in materials with quenched disorder, which may be key to understanding their advanced functionalities.
Phys. Rev. Lett. 134, 256801 (2025)
Crystal melting, Ferroelectricity, Ferroelectrics, Oxides, Cryo-transmission electron microscopy, Scanning transmission electron microscopy
Spin Noise of a Halide Perovskite
Research article | Spin dynamics | 2025-06-24 06:00 EDT
V. O. Kozlov, N. I. Selivanov, C. C. Stoumpos, G. G. Kozlov, V. S. Zapasskii, Yu. V. Kapitonov, D. S. Smirnov, and I. I. Ryzhov
We report on the first observation of spin noise in a strongly birefringent semiconductor—halide perovskite single crystal ${\mathrm{MAPbI}}{3}$. The observed spin noise resonance is attributed to resident free holes in the bulk of the crystal with one of the longest spin dephasing times ${T}{2}=4\text{ }\text{ }\mathrm{ns}$. The spin dynamics is found to be affected by the residual light absorption of the crystal providing renormalization of the Larmor frequency. Extended spin noise spectroscopy with a rotating magnetic field allowed us not only to evaluate the $g$-factor anisotropy but also to distinguish two different spin subsystems tentatively associated with twinning of the crystal. This work opens the way to studies of spin physics of bulk anisotropic semiconductors in general and perovskites in particular.
Phys. Rev. Lett. 134, 256901 (2025)
Spin dynamics, Semiconductor compounds, Single crystal materials, Electron-correlation calculations, Spin noise spectroscopy
Review of Modern Physics
Spin-dependent exotic interactions
Research article | Atomic spectra | 2025-06-24 06:00 EDT
Lei Cong, Wei Ji, Pavel Fadeev, Filip Ficek, Min Jiang, Victor V. Flambaum, Haosen Guan, Derek F. Jackson Kimball, Mikhail G. Kozlov, Yevgeny V. Stadnik, and Dmitry Budker
This review presents a comprehensive summary of theoretical investigations and experimental searches for spin-dependent interactions beyond the standard model. These interactions may be mediated by various types of exotic bosons, and their existence and properties may, in turn, explain the nature of dark matter and dark energy. The described experiments also probe the discrete fundamental symmetries of nature.
Rev. Mod. Phys. 97, 025005 (2025)
Atomic spectra, Fine & hyperfine structure, Particle interactions, Quantum gravity, Quantum optics, Signatures with new bosons, Chiral symmetry, Dark matter detectors
arXiv
Engineering deterministic, tunable, and reversible folds in graphene with the use of ultrafast laser micro-patterned stretchable polymer substrate
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
A.F. Juarez Saborio, F. Bourquard, R. Galafassi, A. Claudel, L. Marty, A. Piednoir, M. Mercury, R. Fulcrand, C. Albin, V. Barnier, F. Garrelie, A. San-Miguel, F. Vialla
The unique atomic monolayer structure of graphene gives rise to a broad range of remarkable mechanical folding properties. However, significant challenges remain in effectively harnessing them in a controllable and scalable manner. In this study, we introduce an innovative approach that employs micron-scale cavities, fabricated through ultrafast laser patterning, in a stretchable polymer substrate to locally modulate adhesion and strain transfer to a graphene monolayer. This technique enables the deterministic induction of single folds in graphene with fold dimensions, width and height in the hundreds of nanometers, tunable through the geometry of the polymer cavities and the applied strain. Importantly, these folds are reversible, returning to a flat morphology with minimal structural damage, as confirmed by Raman spectroscopy. Additionally, our method allows for the creation of fields of folds with reproducible periodicity, defining clear potential for practical applications. These findings pave the way for the development of advanced devices that would leverage the strain and morphology-sensitive properties of graphene.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Bootstrapping Flat-band Superconductors: Rigorous Lower Bounds on Superfluid Stiffness
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Qiang Gao, Zhaoyu Han, Eslam Khalaf
The superfluid stiffness fundamentally constrains the transition temperature of superconductors, especially in the strongly coupled regime. However, accurately determining this inherently quantum many-body property in microscopic models remains a significant challenge. In this work, we show how the \textit{quantum many-body bootstrap} framework, specifically the reduced density matrix (RDM) bootstrap, can be leveraged to obtain rigorous lower bounds on the superfluid stiffness in frustration free models with superconducting ground state. We numerically apply the method to a special class of frustration free models, which are known as quantum geometric nesting models, for flat-band superconductivity, where we uncover a general relation between the stiffness and the pair mass. Going beyond the familiar Hubbard case within this class, we find how additional interactions, notably simple intra-unit-cell magnetic couplings, can enhance the superfluid stiffness. Furthermore, the RDM bootstrap unexpectedly reveals that the trion-type correlations are essential for bounding the stiffness, offering new insights on the structure of these models. Straight-forward generalization of the method can lead to bounds on susceptibilities complementary to variational approaches. Our findings underscore the immense potential of the quantum many-body bootstrap as a powerful tool to derive rigorous bounds on physical quantities beyond energy.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
5-page main text with three figures
High spin, low spin or gapped spins: magnetism in the bilayer nickelates
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Hanbit Oh, Yi-Ming Wu, Julian May-Mann, Yijun Yu, Harold Y. Hwang, Ya-Hui Zhang, S. Raghu
Inspired by the recent discovery of high-temperature superconductivity in bilayer nickelates, we investigate the role of magnetism emerging from a hypothetical insulating $ d^8$ parent state. We demonstrate that due to the interplay of superexchange and Hund’s coupling, the system can be in a high-spin, low-spin or spin-gapped state. The low-spin state has singlets across the bilayer in the $ d_{z^2}$ orbital, with charge carriers in the $ d_{x^2-y^2}$ orbital. Thus, at low energy scales, it behaves as an effective one band system when hole doped. By contrast, the high-spin state is a more robust, spin-1 antiferromagnet. Using Hartree-Fock methods, we find that for fixed interaction strength and doping, high-spin magnetism remains more robust than the low-spin counterpart. Whether this implies that the high spin state provides a stronger pairing glue, or more strongly competes with superconductivity remains an open question. Our analysis therefore underscores the importance of identifying the spin state for understanding superconductivity in nickelates.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
7+9 pages, 4+5 figures, 0+1 tables
Pseudo-chiral phonon splitting from octupolar magnetic order
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Ruairidh Sutcliffe, Kathleen Hart, Swati Chaudhary, Arun Paramekanti
Motivated by the recent discovery of anomalously large magnetic response of chiral phonons in dipolar magnets, we explore an extension to study Einstein quantum phonon modes coupled to multipolar moments. We consider the case of non-Kramers $ \Gamma_3$ doublets which encapsulate quadrupolar and Ising octupolar degrees of freedom, and which feature a symmetry-allowed linear coupling between local quadrupolar moments and Raman active $ E_g$ phonon modes $ (d_{x^2-y^2},d_{3z^2-r^2})$ . We show that either octupolar or quadrupolar ordering leads to degeneracy breaking of the $ E_g$ phonon doublet, with ferro-octupolar order favoring pseudo-chiral phonon eigenmodes with a detectable energy splitting. We describe this physics using a path integral approach in the limit where fast' phonon modes sense the slow’ pseudospins as a static background which we average over using Monte Carlo simulations. We discuss implications for materials such as Ba$ _2$ CaOsO$ _6$ and PrV$ _2$ Al$ _{20}$ where Raman spectroscopy of phonons could be used as a potential probe of hidden octupolar order. Our work extends the important concept of chiral phonons to a large class of multipolar magnets.
Strongly Correlated Electrons (cond-mat.str-el)
5 pages, 4 figures + 6 pages SM
Strong Correlations, Green’s Function Zeros and Topological Transitions in Orbital-Symmetry-Controlled Chemical Reactions
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Ziren Xie, Amir Mirzanejad, Lukas Muechler
We integrate concepts from topological band theory and strong-correlation physics with the principle of orbital symmetry conservation, which characterizes reactions as symmetry allowed or forbidden based on whether molecular orbitals cross along the reaction coordinate. Using a $ 4\pi$ electrocyclization as an example, we show how Green’s functions generalize the concepts of symmetry allowed and symmetry forbidden reactions even in the presence of strong multi-reference correlations. We demonstrate how symmetry forbidden reactions are characterized by strong multi-reference correlations, resulting in crossings of Green’s function zeros rather than poles as MO-theory would predict. Taking into account Green’s functions zeros, a topological invariant is introduced that captures symmetry protected crossings of poles or zeros. We discuss the effects of symmetry breaking and outline generalizations of our approach to reactions without any conserved spatial symmetries along the reaction path. Our work lays the groundwork for systematic application of modern topological methods to chemical reactions and can be generalized to reactions involving different spin states or to excited states.
Strongly Correlated Electrons (cond-mat.str-el), Chemical Physics (physics.chem-ph)
comments welcome
Superconductivity on the edge of vanishing magnetic order
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-25 20:00 EDT
Zhiqiang Wang, Ke Wang, K. Levin
There should be no question that magnetism and superconductivity appear in close proximity in many if not most of the unconventional superconductors. These two phases are importantly correlated: the strongest manifestations of this superconducting pairing are generally associated with the weakest magnetism. It is often stated that this behavior results from a quantum critical point (QCP), although not all such superconductors fit into this category. In this paper we consider a second scenario for addressing these proximity phenomena in which no QCP is present. Although there are other examples for this latter category, most notable are those associated with very strongly paired superconductors that have insulating and magnetically ordered parent" materials. Here, too, one finds that failed” long range order is key to establishing superconductivity. This leads to the general question, which is the focus of this paper. Why, and how, in either of these contexts, does this proximal magnetism play a constructive role in helping to stabilize superconductivity? Our understanding here should help pave the way towards the discovery of new families of superconductors, which are expected to emerge on the brink of magnetism.
Superconductivity (cond-mat.supr-con)
20 pages, 4 figures
Nonequilibrium Theory for Adaptive Systems in Varying Environments
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-25 20:00 EDT
Ying-Jen Yang, Charles D. Kocher, Ken A. Dill
Biological organisms thrive by adapting to their environments, which are often unpredictably changeable. We apply recent results from nonequilibrium physics to show that organisms’ fitness parses into a static generalist component and a nonequilibrium tracking component. Our findings: (1) Environmental changes that are too fast or too small are not worth tracking. (2) Well-timed anticipatory tracking enhances fitness in coherent environments. (3) We compute and explain the optimal adaptive strategy for a system in a given environment, such as bet hedging or phenotypic memory. Conversely, (4) We compute and explain the optimal way for an environment to control a given system, for example for designing drug regimens to limit the growth of pathogens. By connecting fitness, adaptive strategy, and environmental variability, this work provides the foundations for a generic physical theory of adaptivity.
Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph), Populations and Evolution (q-bio.PE)
Dynamics of Phase-Separated Interfaces in Inhomogenous and Driven Mixtures
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-25 20:00 EDT
Jacopo Romano, Ramin Golestanian, Benoît Mahault
We derive effective equations of motion governing the dynamics of sharp interfaces in phase-separated binary mixtures driven by spatio-temporal modulations of their material properties. We demonstrate, in particular, that spatial heterogeneities in the surface tension induce an effective capillary force that drives the motion of interfaces, even in the absence of hydrodynamics. Applying our sharp interface model to quantify the dynamics of thermophoretic droplets, we find that their deformation and transport properties are controlled by a combination of bulk and capillary forces, whose relative strength depends on droplet size. Strikingly, we show that small thermophobic droplets – composed of a material with a positive Soret coefficient – can spontaneously migrate towards high-temperature regions as a result of capillary forces.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
11 pages, 3 figures
Discovery of magnon self-interaction in a strongly driven antiferromagnet
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
David Rohrbach, Zhuquan Zhang, Takayuki Kurihara, Keith A. Nelson
Nonlinear dynamics govern a wide array of natural phenomena and are essential for understanding nonequilibrium behaviors in condensed matter systems. In magnetically ordered materials, magnons - the quanta of spin waves - exhibit intrinsic nonlinearities that are of great interest in fundamental research and practical applications. Despite progress in the nonlinear control of magnon modes in antiferromagnetic materials, the transition from perturbative to non-perturbative regimes of magnon coherences has remained elusive. Here, we explore the nonlinear dynamics of a magnon mode in an antiferromagnet using two-dimensional terahertz spectroscopy with waveguide-enhanced terahertz fields. By driving the magnon mode far from equilibrium, we demonstrate the emergence of high-order magnon coherences and delineate a distinct transition into non-perturbative magnon nonlinearities. This behavior originates from the intrinsic anharmonicity of the magnetic potential and marks a regime dominated by magnon self-interactions at large spin deflection angles. These findings provide fundamental mechanistic insights that might be exploited for ultrafast switching and other advanced magnonic applications.
Materials Science (cond-mat.mtrl-sci)
Supercurrent-induced antiferromagnetic order and spin-triplet pair generation in quantum critical d-wave superconductors
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-25 20:00 EDT
Kyohei Nakamura, Youichi Yanase
A supercurrent is well recognized as being of prime importance within mean-field theory, but remains largely unexplored in strongly correlated electron systems (SCES) and the quantum critical region. To clarify the impact of the supercurrent on magnetism and superconductivity near an antiferromagnetic quantum critical point, we study the two-dimensional Hubbard model based on a fluctuation exchange approximation for a current-carrying superconducting state. We show a supercurrent-induced antiferromagnetism and emergence of spin-triplet Cooper pairs. The former results from Bogoliubov Fermi surfaces, suppression in the superconducting gap, and strong correlation effects beyond the mean-field theory. Our results suggest that the supercurrent can bring out rich phenomena of superconductivity in SCES.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
Emergent collective dynamics from motile photokinetic organisms
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-25 20:00 EDT
J. Morales, P. Munoz, D. Noto, H.N Ulloa, F. Guzman-Lastra
The day-night cycle drives the largest biomass migration on Earth: the diel vertical migration (DVM) of aquatic organisms. Here, we present a three-dimensional agent-based model that incorporates photokinesis, gyrotaxis, and stochastic reorientation to explore how individual-level swimming behaviors give rise to population-scale DVM patterns. By solving Langevin equations for swarms of swimmers, we identify four distinct regimes – Surface Accumulation, Shallow DVM, Deep DVM, and Sinking – governed by two key dimensionless parameters: the Peclet number (Pe), representing motility persistence, and the vertical swimming asymmetry ratio (W=wdown/wup), encoding photokinetic bias. These regimes emerge from nonlinear interactions between light-driven navigation and active noise, diagnosed through topological and statistical features of vertical distributions. A critical feedback is uncovered: upward-biased swimming (W<1) promotes surface aggregation, while excessive downward bias (W>1) leads to irreversible sinking. Analytical estimates link regime boundaries to gyrotactic alignment and velocity reversals. Together, our results provide a mechanistic framework to interpret DVM diversity and emphasize the central role of light gradients-beyond absolute intensity-in shaping ecological self-organization.
Soft Condensed Matter (cond-mat.soft)
11 pages 5 Figures
Future prospect of anisotropic 2D tin sulfide (SnS) for emerging electronic and quantum device applications
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
The family of anisotropic two-dimensional (2D) emerging materials is rapidly evolving due to their low crystal symmetry and in-plane structural anisotropy. Among these, 2D tin sulfide (SnS) has gained significant attention because of its distinctive crystalline symmetry and the resulting extraordinary anisotropic physical properties. This perspective explores recent developments in anisotropic 2D SnS. In particular, it highlights advances in isolating high-quality SnS monolayers (1L-SnS) and in applying advanced techniques for anisotropic characterization. The discussion continues with an overview of the anisotropic optical properties of SnS, followed by recent progress in emerging electronic device applications, including energy storage, neuromorphic (synaptic) systems, and quantum technologies. In addition to presenting significant research findings on SnS, this perspective outlines current limitations and discusses emerging opportunities and future prospects for its application in quantum devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph), Optics (physics.optics), Quantum Physics (quant-ph)
Localization and splitting of a quantum droplet by immersing a heavy impurity
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-25 20:00 EDT
F. Bristy, G. A. Bougas, G. C. Katsimiga, S. I. Mistakidis
We unravel the existence and nonequilibrium response of one-dimensional harmonically trapped droplet configurations in the presence of a central repulsive or attractive potential well mimicking the effect of a heavy impurity. For fixed negative chemical potentials, it is shown that droplets fragment into two for increasing repulsive potential heights, a process that occurs faster for larger widths. However, atoms from the droplet accumulate at the attractive potential, especially for wider ones, leading to a deformed droplet and eventually to the termination of the solution. Linearization analysis yields the underlying excitation spectrum which dictates stability and the behavior of the ensuing collective modes. Quenches in the potential height are used to demonstrate dynamical fragmentation of the droplet for repulsive potentials as well as self-evaporation along with droplet localization and eventual relaxation for longer evolution times in the case of attractive potential wells. The many-body character of the dynamics is explicated by evaluating the participating single-particle eigenstates manifesting the superposition nature of the droplet state. Our results should be detectable by current ultracold atom experiments and may inspire engineered droplet dynamics with the aid of external potentials.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph), Quantum Physics (quant-ph)
13 pages, 8 figures
A Novel Analysis Framework for Microstructural Characterization of Ferroelectric Hafnia: Experimental Validation and Application
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
Yoonsang Park, Jaeduck Jang, Hyangsook Lee, Kihong Kim, Kyooho Jung, Yunseong Lee, Jaewoo Lee, Eunji Yang, Sanghyun Jo, Sijung Yoo, Hyun Jae Lee, Donghoon Kim, Duk-Hyun Choe, Seunggeol Nam
Herein, we present a novel analysis framework for grain size profile of ferroelectric hafnia to tackle critical shortcomings inherent in the current microstructural analysis. We vastly enhanced visibility of grains with ion beam treatment and performed accurate grain segmentation using deep neural network (DNN). By leveraging our new method, we discovered unexpected discrepancies that contradict previous results, such as deposition temperature (Tdep) and post-metallization annealing (PMA) dependence of grain size statistics, prompting us to reassess earlier interpretations. Combining microstructural analysis with electrical tests, we found that grain size reduction had both positive and negative outcomes: it caused significant diminishing of die-to-die variation (~68 % decrease in standard deviation) in coercive field (Ec), while triggering an upsurge in leakage current. These uncovered results signify robustness of our method in characterization of ferroelectric hafnia for in-depth examination of both device variability and reliability.
Materials Science (cond-mat.mtrl-sci)
4 pages (2 pages are text rest are filled with figures)
Controlling Topological Quantum Transport via Non-Perturbative Light-Matter Interaction in Disordered Systems
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
Jorge Martinez Romeral, Luis M.Canonico, Aron W.Cummings, Stephan Roche
We report the possibility to induce topological quantum transport in otherwise trivial systems through non-perturbative light-matter interactions, as well as the enhancement of this effect in the presence of disorder. Going beyond prior theoretical approaches, we introduce a computational framework which performs large-scale real-space quantum dynamics simulations, including carrier thermalization and disorder effects, in systems driven out of equilibrium by light or other external interactions. This methodology is illustrated in gapped single-layer and Bernal bilayer graphene but can be implemented in arbitrarily complex systems, including disordered and aperiodic systems, opening novel avenues for the design of multifunctional topological electronic devices that work in far-from-equilibrium regimes.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
4 pages, 3 figures
Hidden Bose-Einstein Singularities in Correlated Electron Systems: III. Thermodynamic Signals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
We study thermodynamic consequences of the hidden Bose-Einstein singularities, which have been predicted to cause a pseudogap phase, based on quantum field theory of ordered phases. Starting from the Luttinger-Ward functional for the grand thermodynamic potential, we derive expressions of the Helmholtz free energy, internal energy, entropy, and heat capacity in a form suitable for numerical studies. They are applied to the weakly attractive Hubbard model in three dimensions to calculate the thermodynamic potentials numerically and continuously for the normal, pseudogap, and superconducting phases on the same footing. It is shown that the entry into the pseudogap phase is detectable as singularities of thermodynamic potentials, especially a discontinuity in the heat capacity.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Gases (cond-mat.quant-gas), Superconductivity (cond-mat.supr-con)
9 pages, 4 figures
High Pressure Growth of Transition-Metal Monosilicide RhGe Single Crystals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Xiangjiang Dong, Bowen Zhang, Xubin Ye, Peng Wei, Lie Lian, Ning Sun, Youwen Long, Shangjie Tian, Shouguo Wang, Hechang Lei, Runze Yu
Transition-metal monosilicide RhGe has been reported to exhibit weak itinerant ferromagnetism, superconductivity, and topological properties. In this study, we report the high-pressure growth of high-quality RhGe single crystals up to millimeter size using flux method. Transport measurements reveal the metallic behavior of RhGe between 2-300 K with Fermi liquid behavior at low temperature region. However, no superconductivity was observed with variations in Ge composition. Magnetic characterizations indicate that RhGe exhibits a paramagnetic behavior between 2-300 K. The high-quality, large-size RhGe single crystals pave the way for further investigation of their topological properties using spectroscopic techniques.
Strongly Correlated Electrons (cond-mat.str-el)
Chin.Phys.B accepted
Simulation of Flagellated Bacteria Near a Solid Surface: Effects of Flagellar Morphology and Ionic Strength
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-25 20:00 EDT
This study systematically investigates the dynamics of the bacterial transition from free-swimming to surface adhesion, a process characterized by both height $ h$ and inclination angle $ \Psi$ . The surface entrapment process is divided into three main stages. Initially, bacteria swim towards the surface at an approach velocity proportional to the motor rotation frequency. Subsequently, during the reorientation stage, the cotangent of the inclination angle decays exponentially with the product of the motor rotation frequency and time. Finally, the combined effect of near-field hydrodynamic interactions and DLVO forces drives the bacteria to a stable fixed point $ (h^{\ast},\Psi^{\ast})$ near the surface. Bacteria with left-handed chiral flagella exhibit clockwise circular motion on the surface. The stable height, inclination angle, and radius of curvature of these circular trajectories are collectively determined by the flagellar morphology and ionic strength of the electrolyte solution. More precisely, increasing the contour length of the flagellum decreases the stable inclination angle and increases the radius of curvature. In contrast, decreasing the ionic strength increases the stable height and radius of curvature, while also decreasing the stable inclination angle. Typically, the stable inclination angle falls within $ (\pi/2,\pi)$ , the stable height ranges from a few nanometers to approximately one hundred nanometers, and the radius of curvature of the circular motion spans several to tens of micrometers.
Soft Condensed Matter (cond-mat.soft)
Effect of Berry connection on attosecond transient absorption spectroscopy in gapped graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
Jiayu Yan, Hongxuan Er, Wei Dang, Jiahuan Ren, Chao Chen, Dianxiang Ren, Fulong Dong
We investigated the attosecond transient absorption spectroscopy (ATAS) in gapped graphene by numerically solving the four-band density-matrix equations. Our results reveal that, in contrast to graphene whose fishbone-shaped spectra primarily oscillates at twice the frequency of the pump laser, the ATAS of gapped graphene exhibits a first-order harmonic component induced by the Berry connection. To gain insight into this interesting results, we employ a simplified model that considers only the nonequivalent electrons at $ \Gamma$ and $ \textrm{M}$ points in the Brillouin zone. This model allows us to derive an analytical expression for the ATAS contribution stemming from the Berry connection. Our analytical results qualitatively reproduce the key features observed in the numerical simulations, and reveal that the first-order harmonic component of spectra arises ont only from the Berry connections but also from the energy shifts associated with the effective mass of electrons at the $ \Gamma$ and $ \textrm{M}$ points. These results shed light on the complex generation mechanism of the ATAS in symmetry-broken materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Atomic Physics (physics.atom-ph)
Very strong coupling limit of Eliashberg-McMillan theory and the upper limit for superconducting transition temperature
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-25 20:00 EDT
We present a brief review of some recent work on the problem of highest achievable temperature of superconducting transition $ T_c$ in electron-phonon systems. The discovery of record-breaking values of $ T_c$ in quite a number of hydrides under high pressure was an impressive demonstration of capabilities of electron-phonon mechanism of Cooper pairing. This lead to an increased interest on possible limitations of Eliashberg-McMillan theory as the main theory of superconductivity in a system of electrons and phonons. We shall consider some basic conclusions following from this theory and present some remarks on the limit of very strong electron-phonon coupling. We shall discuss possible limitations on the value of the coupling constant related to possible lattice and specific heat instability and conclude that within the stable metallic phase the effective pairing constant may acquire very large values. Finally we discuss some bounds for $ T_c$ derived in the strong coupling limit and propose an elementary estimate of an upper limit for $ T_c$ , expressed via combination of fundamental physical constants.
Superconductivity (cond-mat.supr-con)
14 pages, 4 figures, submitted to the special issue of Annalen der Physik, dedicated to the memory of Mikhail Eremets. arXiv admin note: substantial text overlap with arXiv:2106.09948
Dynamics of Cu$_2$O Rydberg excitons – real density matrix approach
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
Karol Karpinski, Gerard Czajkowski
Basing on recent reliable measurements of the life- and coherence time of Cu$ _2$ O Rydberg excitons, we present an analytical method which enables to describe the experimental results. The real-density matrix approach (RDMA) is applied to describe two-photon absorption in Cu$ _2$ O through the excitonic response to the exciting fields. This approach produces an analytical expression for the emission intensity time evolution, and can be used to explain trends in reported experimental data. Our approach takes into account the effect of the coherence between the electron-hole pair and the electromagnetic fields, the quantum beats and the life- and coherence time dependence on the applied laser power. Adding a separation of slow- and rapid dynamics components we find excellent agreement with the experimental data.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
16 pages, 7 figures
Efficient optimization of variational tensor-network approach to three-dimensional statistical systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-25 20:00 EDT
Xia-Ze Xu, Tong-Yu Lin, Guang-Ming Zhang
Variational tensor network optimization has become a powerful tool for studying classical statistical models in two dimensions. However, its application to three-dimensional systems remains limited, primarily due to the high computational cost associated with evaluating the free energy density and its gradient. This process requires contracting a triple-layer tensor network composed of a projected entangled pair operator and projected entangled pair states. In this paper, we employ a split corner-transfer renormalization group scheme tailored for the contraction of such triple-layer networks, which reduces the computational complexity from $ \mathcal{O}(D^{12})$ in conventional methods to $ \mathcal{O}(D^{9})$ . Through numerical benchmarks on the three-dimensional classical Ising model, we demonstrate that the proposed scheme achieves numerical results comparable to the most recent Monte Carlo simulations, while also providing a substantial speedup over previous variational tensor network approaches. This makes this method well-suited for efficient gradient-based optimization in three-dimensional tensor network simulations.
Statistical Mechanics (cond-mat.stat-mech)
13 pages, 16 figures
Tunable phase transitions from semimetals to Chern insulators in two-dimensional quadratic-band-crossing materials
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
We systematically investigate how static symmetry-breaking perturbations and dynamic Floquet terms via a polarized light manipulate the topological phase transitions in the two-dimensional quadratic-band-crossing-point (QBCP) materials. The Berry curvature shows distinct behavior in such two situations. It is linearly and quadratically proportional to the product of microstructural parameters $ t_{x,z}$ for the former and the latter, respectively. The static perturbation eliminates the QBCP and opens an energy gap, which leads to the momentum-inversion symmetry of Berry curvature. This yields a nontrivial Chern number determined by the microstructural parameters. In contrast, we demonstrate that either a circularly or an elliptically polarized light breaks the time-reversal symmetry, transforming the QBCP semimetal into a Chern insulator with a quantized anomalous Hall conductivity $ \sigma_{xy} = Ce^2/\hbar$ , where the Chern number is governed by the polarization angle. Moreover, the linear polarization preserves the central antisymmetry of the Berry curvature, giving rise to a topological trivial insulator. These results establish a tunable topological phase transition from a QBCP semimetal to Chern insulator in the two-dimensional QBCP materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
14 pages, 10 figures
Exchange-correlation torques from gauge symmetries
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
Jacques K. Desmarais, Kamel Bencheikh, Giovanni Vignale, Stefano Pittalis
The problem of predicting accurate exchange-correlation (xc) spin-torques in non-collinear magnetic systems has dominated the scene of spin-density functional theory (SDFT) in the last two decades. Progress has been hindered by the fact that the spin torque is directly connected to the divergence of the spin current, a quantity that is extraneous to SDFT. Furthermore, SDFT does not apply in the presence of vector potentials and spin-orbit couplings. Here, we propose a solution that exploits the physical implications of the U(1)xSU(2) gauge invariance of the xc energy in SpinCurrent-DFT. We derive explicit xc torque expressions based on meta-generalized-gradient approximations in the framework of the generalized Kohn-Sham (GKS) formulation. One key term represents an xc-torque involving the GKS spin-kinetic energy density; and another term resembles the phenomenological spin current of the Landau-Lifshitz equations: both are derived from first-principles. We also show that the functional form ensures that the GKS particle- and spin-currents are identical, in form, to their interacting counterparts. Non-collinear equilibrium conditions and adiabatic dynamics are thus derived that resolve longstanding issues.
Materials Science (cond-mat.mtrl-sci), Atomic and Molecular Clusters (physics.atm-clus), Chemical Physics (physics.chem-ph)
Towards a two-scale model for morphogenesis – How cellular processes influence tissue deformations
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-25 20:00 EDT
We propose a two-scale model to resolve essential features of developmental tissue deformations. The model couples individual cellular behavior to the mechanics at tissue scale. This is realized by a multiphase-field model addressing the motility, deformability and interaction of cells on an evolving surface. The surface evolution is due to bending elasticity, with bending properties influenced by the topology of the cellular network, which forms the surface. We discuss and motivate model assumptions, propose a numerical scheme, which essentially scales with the number of cells, and explore computationally the effect of the two-scale coupling on the global shape evolution. The approach provides a step towards more quantitative modeling of morphogenetic processes.
Soft Condensed Matter (cond-mat.soft), Mathematical Physics (math-ph)
31 pages, 17 figures
Rare-earth atoms on Nb(110) as a platform to engineer topological superconductivity
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-25 20:00 EDT
David Antognini Silva, Yu Wang, Nicolae Atodiresei, Felix Friedrich, Stefan Blügel, Matthias Bode, Philipp Rüßmann, Artem Odobesko
Helical spin textures in one-dimensional magnetic chains on superconductors can enable topological superconductivity and host Majorana zero modes, independent of the presence of intrinsic spin-orbit coupling. Here, we show that gadolinium (Gd) adatoms, possessing large 4f magnetic moments when placed on a Nb(110) surface, establish indirect exchange interactions mediated by valence electrons, manifesting as Yu-Shiba-Rusinov states. By combining scanning tunneling microscopy and spectroscopy with density functional theory, we analyze the emergence of the Yu-Shiba-Rusinov states in single Gd atoms and Gd dimers and uncover the underlying magnetic interaction mechanisms, on the basis of which we predict by means of spin-dynamics simulations the formation of stable chiral Néel-type spin-spiral configurations in Gd chains. These findings highlight rare-earth magnets as a promising platform for precisely tuning spin-spiral ground states, an essential prerequisite for the realization of topological superconductivity.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 5 figures
Long-term atomistic finite-temperature substitutional diffusion
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
Shashank Saxena, Prateek Gupta, Dennis M. Kochmann
Simulating long-term mass diffusion kinetics with atomic precision is important to predict chemical and mechanical properties of alloys over time scales of engineering interest in applications, including (but not limited to) alloy heat treatment, corrosion resistance, and hydrogen embrittlement. We present a new strategy to bridge from the time scale of atomic vibrations to that of vacancy-mediated atomic hops by a combination of statistical mechanics-based Gaussian phase packets (GPP) relaxation and a nudged elastic band (NEB)-facilitated harmonic transition state theory (H-TST) time update. We validate the approach by simulating bulk self-diffusion in copper and the segregation of vacancies and magnesium to a stacking fault and a symmetric tilt grain boundary in aluminum, modeled with an embedded atom method (EAM) potential. The method correctly predicts the kinetics in bulk copper and equilibrium impurity concentrations in aluminum, in agreement with the Langmuir-Mclean solution in the dilute limit. Notably, this technique can reach realistic diffusion time scales of days, weeks, and even years in a computational time of hours, demonstrating its capability to study the long-term chemo-thermo-mechanically coupled behavior of atomic ensembles.
Materials Science (cond-mat.mtrl-sci)
Elastic heterogeneity governs anomalous scaling in a soft porous crystal
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-25 20:00 EDT
Nanoscale molecular transport plays a crucial role in regulating mass diffusion and responsiveness in condensed matter systems. In soft porous crystals, in particular, adsorption of guest molecules induces host framework deformation and changes in rigidity, underpinning their characteristic stimuli-responsive behaviour. Surface-mediated adsorption leads to inhomogeneous adsorbate distribution, which, through local framework deformation, induces spatial variations in rigidity – elastic heterogeneity. Although this heterogeneity is expected to affect adsorption kinetics and mechanical behaviour, its role remains poorly understood. Here we show that elastic heterogeneity governs adsorption kinetics, leading to emergent phenomena including size-dependent uptake, surface creasing, and anomalous dynamic scaling that is distinct from established scaling. Stress relaxation near corners facilitates adsorption, resulting in a size-dependent deviation from diffusive kinetics. Away from corners, flexible unadsorbed regions between rigid adsorbed domains relieve stress through crease formation. The resulting lateral correlations exhibit anomalous dynamic scaling, characterized by a breakdown of scale invariance between global and local interfacial fluctuations. These findings provide a mechanistic foundation for controlling adsorption and deformation kinetics in soft porous materials via elastic heterogeneity. Our work opens a route to engineering responsive materials, where mechanical feedback is harnessed to control cooperative molecular transport and drive macroscopic shape changes under external perturbations.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech)
12 pages, 4 figures, and 10 extended data figures
Tailoring Magnetic Properties of Zigzag Structured Thin Films via Interface Engineering and Columnar Nano-structuring
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
Sharanjeet Singh, Manisha Priyadarsini, Anup Kumar Bera, Smritiparna Ghosh, Varimalla R. Reddy, Sarathlal Koyiloth Vayalil, Benedikt Sochor, Dileep Kumar
We report the emergence of a novel interface-induced shape anisotropy component in zigzag-structured thin films fabricated via Sequential Oblique Angle Deposition (S-OAD). In this study, we systematically investigate cobalt (Co) and Co2FeAl (CFA) thin films by varying column length, number of bilayers, and magneto-crystalline anisotropy (MCA) to explore how structural modulation affects magnetic behavior. Using magneto-optical Kerr effect (MOKE) measurements in conjunction with synchrotron-based grazing-incidence small-angle X-ray scattering (GISAXS) and 2D X-ray diffraction (2DXRD), we reveal that the interplay between interface-induced, shape, and crystalline anisotropies allows for a tunable magnetic response, ranging from isotropic to anisotropic behavior. The observed uniaxial magnetic anisotropy (UMA) exceeds that of conventional OAD films, while column merging is effectively suppressed through precise multilayer engineering. Structural analysis confirms that periodic, high-density interfaces at the junctions of oppositely tilted columns are central to this anisotropy control. These findings demonstrate that interface engineering and columnar nanostructuring within zigzag nanostructures offer a powerful route for tailoring magnetic properties in zigzag thin films, enabling their application in next-generation spintronic and magnetic sensor technologies.
Materials Science (cond-mat.mtrl-sci)
21 pages, 10 figures
Machine Learning Accelerates Raman Computations from Molecular Dynamics for Materials Science
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
David A. Egger, Manuel Grumet, Tomáš Bučko
Raman spectroscopy is a powerful experimental technique for characterizing molecules and materials that is used in many laboratories. First-principles theoretical calculations of Raman spectra are important because they elucidate the microscopic effects underlying Raman activity in these systems. These calculations are often performed using the canonical harmonic approximation which cannot capture certain thermal changes in the Raman response. Anharmonic vibrational effects were recently found to play crucial roles in several materials, which motivates theoretical treatments of the Raman effect beyond harmonic phonons. While Raman spectroscopy from molecular dynamics (MD-Raman) is a well-established approach that includes anharmonic vibrations and further relevant thermal effects, MD-Raman computations were long considered to be computationally too expensive for practical materials computations. In this perspective article, we highlight that recent advances in the context of machine learning have now dramatically accelerated the involved computational tasks without sacrificing accuracy or predictive power. These recent developments highlight the increasing importance of MD-Raman and related methods as versatile tools for theoretical prediction and characterization of molecules and materials.
Materials Science (cond-mat.mtrl-sci)
Entanglement and quench dynamics in the thermally perturbed tricritical fixed point
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-25 20:00 EDT
We consider the Blume-Capel model in the scaling limit to realize the thermal perturbation of the tricritical Ising fixed point. We develop a numerical scaling-limit extrapolation for one-point functions and Rényi entropies in the ground state. In a mass quench scenario, we found long-living oscillations despite the absence of explicit spin-flip symmetry breaking or confining potential. We construct form factors of branch-point twist fields in the paramagnetic phase. In the scaling limit of small quenches, we verify form factor predictions for (i) the energy density and leading magnetic field using the dynamics of one-point functions, and (ii) branch-point twist fields using the dynamics of Rényi entropies.
Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
37 pages, 10 figures, 12 tables
Effective Interactions in Quasi-One-Dimensional Dipolar Quantum Gases
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-25 20:00 EDT
Michał Zdziennicki, Mateusz Ślusarczyk, Krzysztof Pawłowski, Krzysztof Jachymski
Ultracold dipolar atoms and molecules provide a flexible quantum simulation platform for studying strongly interacting many-body systems. Determining microscopic Hamiltonian parameters of the simulator is crucial for it to be useful. We study effective interactions emerging in quasi-one-dimensional (q1D) dipolar quantum gases, revealing significant nonuniversal corrections to the commonly used 1D pseudopotential. We demonstrate that a full 3D treatment employing realistic interaction potentials is essential for describing the reduced-dimensional system. Our findings are particularly relevant to experiments probing excited states and nonequilibrium phenomena.
Quantum Gases (cond-mat.quant-gas)
Long-range Order in a Short-range Quasi-2D XY Model
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-25 20:00 EDT
Minghui Hu, Chao Zhang, Dajun Zhang, Yanan Sun, Youjin Deng, Jian-Ping Lv
The phase of spins in the quasi-two-dimensional (Q2D) XY model has emerged as a topic of significant interest across multiple physics subfields. Here, we propose a short-range (SR) Q2D XY model defined on a plane perpendicularly intersected by a group of parallel planes, with each plane consisting of nearest-neighbor-coupled XY spins. We perform large-scale Monte Carlo simulations to establish the full phase diagram of the Q2D XY model, aided by finite-size scaling. A long-range (LR) ordered phase emerges in the Q2D model when the spins on the parallel planes develop a Berezinskii-Kosterlitz-Thouless critical phase. In the LR ordered phase, ordering is anisotropic: LR correlations develop along the direction of the intersection lines, while critical correlations emerge perpendicular to them. Furthermore, the LR ordered phase exhibits Goldstone-mode physics. Our study hence reveals the existence of LR order in a Q2D XY model with finite SR couplings and opens up a new avenue to explore superfluid orders in low dimensions.
Statistical Mechanics (cond-mat.stat-mech), Quantum Gases (cond-mat.quant-gas), High Energy Physics - Lattice (hep-lat)
17 pages, 9 figures
Valley resolved optical spectroscopy and coherent excitation of quantum Hall edge states in graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
Ashutosh Singh, Maria Sebastian, Mikhail Tokman, Alexey Belyanin
We show that chiral edge states in graphene under Quantum Hall effect conditions can be selectively probed and excited by terahertz or infrared radiation with single-quasiparticle sensitivity without affecting bulk states. Moreover, valley-selective excitation of edge states is possible with high fidelity. The underlying physical mechanism is the inevitable violation of adiabaticity and inversion symmetry breaking for electron states near the edge. This leads to the formation of Landau level-specific and valley-specific absorbance spectral peaks that are spectrally well separated from each other and from absorption by the bulk states, and have different polarization selection rules. Furthermore, inversion symmetry breaking enables coherent driving of chiral edge photocurrents due to second-order nonlinear optical rectification which becomes allowed in the electric dipole approximation.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
11 pages, 9 figures
Probing Phonon Modes in Reconstructed twisted Homo and Hetero Bilayer System
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
Sushil Kumar Sahu, Robin Bajaj, Syed Ummair Ali, Ajay Bhut, Roshan Jesus Mathew, Shinjan Mandal, Kenji Watanabe, Takashi Taniguchi, Manish Jain, Chandan Kumar
Twist angle engineering in van der Waals homo and hetero-bilayers introduces profound modifications in their electronic, optical and mechanical properties due to lattice reconstruction. In these systems, the interlayer coupling and atomic rearrangement strongly depend on the twist angle, leading to the formation of periodic Moire superlattices. At small twist angles, significant lattice relaxation results in the emergence of domain structures separated by one dimensional soliton networks, influencing electronic band structures and phonon modes. Here we systematically investigate the impact of lattice reconstruction on phonon renormalization in twisted bilayer graphene (TBLG,homo) and graphene-hBN Moire superlattices(hetero). Using Raman spectroscopy, we identify distinct phonon behaviours across different twist angle regimes. In TBLG, we observe the evolution of the G peak, including broadening, splitting, and the emergence of additional peaks in the small angle range 0.3 to 1 degree, attributed to Moire modified phonon interactions. At large twist angles, the peaks gradually merge back into a single feature, reflecting the reduced impact of lattice reconstruction. Similarly, in hBN graphene Moire superlattices, we detect Moire induced Raman peaks above and below the G peak, while the central G peak remains largely invariant to twist angle variation. The theoretical calculations uncover Moire phonon modes originating from different stacking regions providing insights into phonon renormalization. Our results establish a direct link between twist angle, lattice reconstruction, Moire phonons, and interlayer coupling, offering a fundamental framework for understanding phonon engineering in twisted bilayer systems. These findings pave the way for controlling phononic, optoelectronic and heat flow properties in next generation van der Waals heterostructures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Decoherence and fidelity enhancement during shuttling of entangled spin qubits
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
Yu-Ning Zhang, Aleksandr S. Mokeev, Viatcheslav V. Dobrovitski
Shuttling of spin qubits between different locations is a key element in many prospective semiconductor systems for quantum information processing, but the shuttled qubits should be protected from decoherence created by time- and space-dependent noises. Since the paths of different spin qubits are interrelated, the noises acting on the shuttled spins exhibit complex and unusual correlations. We appraise the role of these correlations using the concept of trajectories on random sheets, and demonstrate that they can drastically affect efficiency of the coherence protection. These correlations can also be exploited to enhance the shuttling fidelity, and we show that by encoding logical qubit in a state of two consequtively shuttled entangled spins, high fidelity can be achieved even for very slow shuttling. We identify the conditions favoring this encoding, and quantify improvement in the shuttling fidelity in comparison with the single-spin shuttling.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
6 pages, 4 figures
Massive Atomic Diversity: a compact universal dataset for atomistic machine learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
Arslan Mazitov, Sofiia Chorna, Guillaume Fraux, Marnik Bercx, Giovanni Pizzi, Sandip De, Michele Ceriotti
The development of machine-learning models for atomic-scale simulations has benefited tremendously from the large databases of materials and molecular properties computed in the past two decades using electronic-structure calculations. More recently, these databases have made it possible to train universal models that aim at making accurate predictions for arbitrary atomic geometries and compositions. The construction of many of these databases was however in itself aimed at materials discovery, and therefore targeted primarily to sample stable, or at least plausible, structures and to make the most accurate predictions for each compound - e.g. adjusting the calculation details to the material at hand. Here we introduce a dataset designed specifically to train machine learning models that can provide reasonable predictions for arbitrary structures, and that therefore follows a different philosophy. Starting from relatively small sets of stable structures, the dataset is built to contain massive atomic diversity (MAD) by aggressively distorting these configurations, with near-complete disregard for the stability of the resulting configurations. The electronic structure details, on the other hand, are chosen to maximize consistency rather than to obtain the most accurate prediction for a given structure, or to minimize computational effort. The MAD dataset we present here, despite containing fewer than 100k structures, has already been shown to enable training universal interatomic potentials that are competitive with models trained on traditional datasets with two to three orders of magnitude more structures. We describe in detail the philosophy and details of the construction of the MAD dataset. We also introduce a low-dimensional structural latent space that allows us to compare it with other popular datasets and that can be used as a general-purpose materials cartography tool.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
The electronic structure of a doped Mott-Hubbard surface
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Mattia Iannetti, Silvio Modesti, Giovanni Di Santo, Marco Caputo, Polina M. Sheverdyaeva, Paolo Moras, Fabio Chiapolino, Tommaso Cea, Cesare Tresca, Erio Tosatti, Gianni Profeta
The Sn/Si(111)-({\sqrt}3{\times}{\sqrt}3)R30° surface, a 2D Mott insulator, has long been predicted and then found experimetally to metallize and even turn superconducting upon boron doping. In order to clarify the structural, spectroscopic and theoretical details of that evolution, here we present ARPES data supplementing morphology and scanning tunneling measurements. These combined experimental results are compared with predictions from a variety of electronic structure approaches, mostly density functional DFT+U, but not neglecting Mott-Hubbard models, both ordered and disordered. These theoretical pictures address different spectroscopic aspects, including the 2D Fermi surface, the Hubbard bands, etc. While no single picture account for all observations at once,the emergent hypothesis compatible with all data is that metallization arises from sub-subsurface boron doping, additional to the main standard subsurface boron geometry, that would leave the surface insulating. These results advance the indispensable frame for the further understanding of this fascinating system.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
20 pages, 21 figures
Striped excitonic (super)solid in anisotropic semiconductors with screened exciton interactions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
J. F. de Oliveira Neto, F. M. A. Guimarães, Davi S. Dantas, F. M. Peeters, M. V. Milošević, A. Chaves
Within the Gross-Pitaevskii framework, we reveal the emergence of a crystallized phase of an exciton condensate in an atomically-thin anisotropic semiconductor, where screening of exciton-exciton interactions is introduced by a proximal doped graphene layer. While such screened interactions are expected to yield a hexagonal crystal lattice in the excitonic condensate in isotropic semiconductor quantum wells [see e.g. Phys. Rev. Lett. \textbf{108}, 060401 (2012)], here we show that for atomically thin semiconductors with strong electronic anisotropy, such as few-layer black phosphorus, the crystallized exciton phase acquires a parallel stripe structure - unanticipated to date. The optimal conditions for the emergence of this phase, as well as for its coexistence with excitonic superfluidity in a striped supersolid phase, are identified.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Phys. Rev. B 111, L180506 (2025)
Flexoelectric Polarization Enhancement in Paraelectric $\mathrm{BaHfO_3}$ via Strain Gradient Engineering
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
Timo Piecuch, Jeffrey A. Brock, Xiaochun Huang, Arnold M. Müller, Christof Vockenhuber, Christof W. Schneider, Thomas Lippert, Nick A. Shepelin
Flexoelectricity - polarization induced by strain gradients - offers a route to polar functionality in centrosymmetric dielectrics, where traditional piezoelectric effects are absent. This study investigates the flexoelectric effect in epitaxial $ \mathrm{BaHfO_3}$ (BHO) thin films, a centrosymmetric and paraelectric perovskite. While a large lattice mismatch induces defect-driven relaxation, a coherently grown BHO film undergoes elastic relaxation, forming intrinsic strain gradients exceeding $ 10^6\ \mathrm{m}^{-1}$ . A 29-fold enhancement in spontaneous polarization is observed at an electric field of $ 4\ \mathrm{MV,cm}^{-1}$ for BHO exhibiting a strain gradient compared to relaxed BHO. This enhancement is attributed to flexoelectric coupling, which is isolated from ferroelectric and piezoelectric contributions due to the centrosymmetric nature and the absence of phase transitions in BHO. The findings establish a clear link between engineered strain gradients and enhanced polarizability in oxide thin films, offering a benchmark system for deconvoluting the flexoelectric effect from other polar effects. These results provide a basis for exploiting flexoelectricity in dielectric devices and advance the fundamental understanding of strain-coupled phenomena in functional oxides.
Materials Science (cond-mat.mtrl-sci)
Orbital FFLO and layer-selective FFLO phases in trilayer NbSe$_2$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-25 20:00 EDT
Michiya Chazono, Youichi Yanase
Finite-momentum superconductivity has become an important research topic in condensed matter physics. In particular, the orbital Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, which is stabi lized in atomically thin films by the orbital effect of an external magnetic field, has been getting attention as a fascinating finite-momentum superconducting state recently. We study the phase diagram of the trilayer Ising superconductor NbSe$ _2$ in the in-plane magnetic field, taking into ac count the orbital effect, the paramagnetic effect, and the spin-orbit coupling. The finite-momentum gap structure in the high-field region is shown by a large-scale numerical calculation based on the Bogoliubov-de Gennes equation. We find an exotic superconducting phase, a layer-selective FFLO phase, in which finite-momentum Cooper pairs coexist with zero-momentum Cooper pairs, separated from the orbital FFLO phase.
Superconductivity (cond-mat.supr-con)
14 pages, 12 figures
Cluster Spin Glass State in Ba$3$Sb${1+x}$Co${2-x}$O${9-δ}$: Cation Disorder and Mixed-Valence Co Dimers
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Anzar Ali, Guratinder Kaur, Lukas Keller, Masahiko Isobe
We investigate the structural, magnetic, and thermodynamic properties of \BSCO\ ($ x$ = 0.04, $ \delta$ = 0.54), a hexagonal perovskite featuring face-sharing CoO$ _6$ octahedra that forms Co dimers. DC and AC magnetization measurements reveal a frequency-dependent spin-freezing transition consistent with glassy dynamics. AC susceptibility fits best to the Vogel-Fulcher model, indicating collective freezing of interacting spin clusters. Isothermal magnetization follows the Langevin function, suggesting finite-sized magnetic clusters rather than isolated paramagnetic moments. Non-equilibrium dynamics, evidenced by thermoremanent magnetization and memory effects, further support a spin-glass-like state. Heat capacity shows no sharp anomalies, and neutron powder diffraction confirms the absence of magnetic Bragg peaks down to 1.5K, ruling out long-range magnetic order. Rietveld refinement reveals significant Co/Sb intersite disorder ($ \sim$ ~30\pct) and oxygen non-stoichiometry, introducing exchange randomness and frustration that drive the spin-glass-like behavior. Electrical resistivity exhibits Arrhenius-type temperature dependence with an activation energy of 0.173eV, consistent with semiconducting behavior. Temperature-dependent X-ray diffraction shows no structural phase transitions, confirming that the spin-glass-like state is not lattice-driven. Our results establish \BSCO\ as a cluster spin-glass candidate, where Co dimers, disorder, and geometric frustration prevent long-range order, leading to slow spin dynamics. These findings highlight the role of cation disorder and oxygen vacancies in stabilizing unconventional magnetic states in cobalt-based hexagonal perovskites.
Strongly Correlated Electrons (cond-mat.str-el)
Exploring Low-Dimensional Magnetism in Cobalt Vanadates, ${A}$CoV${2}$O${7}$(${A}$=~Ca, Sr) : Crystal Growth and Magnetic Properties of Effective Spin-1/2 Zigzag Chains
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
Anzar Ali, Guratinder Kaur, Arvind Maurya, Isha, Kathrin Küster, Ulrich Starke, Pascal Puphal, Arvind Kumar Yogi, Masahiko Isobe
We report the successful growth of high-quality single crystals of \ACVO, a quasi-one-dimensional zigzag chain compound containing Co$ ^{2+}$ ions, using the optical floating zone method. The crystal growth was stabilized under high-pressure argon-oxygen gas with slow growth rates, overcoming challenges associated with the incongruent melting behavior of this material. X-ray diffraction confirms the zigzag arrangement of Co$ ^{2+}$ ions, forming a quasi-one-dimensional chain structure. Magnetic susceptibility and heat capacity measurements reveal an antiferromagnetic phase transition at the Néel temperature ($ T_{\text{N}} \sim 3.5$ K) and negative Curie-Weiss temperatures, indicative of dominant antiferromagnetic interactions. The distorted CoO$ _6$ octahedral geometry and strong spin-orbit coupling suggest that Co$ ^{2+}$ ions likely exhibit an effective $ J = 1/2 $ Kramers doublet state. The results presented here demonstrate the potential of \ACVO\ as a platform for investigating low-dimensional magnetism and quantum magnetic phenomena. These insights shed light on the role of the $ {A}$ -site ion in tuning the magnetic interactions, which will foster future research into the field-induced behavior in these cobalt vanadates.
Strongly Correlated Electrons (cond-mat.str-el)
Moiré Collapse and Luttinger Liquids In Twisted Anisotropic Homobilayers
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-25 20:00 EDT
D. J. P. de Sousa, Seungjun Lee, Francisco Guinea, Tony Low
We introduce twisted anisotropic homobilayers as a distinct class of moiré systems, characterized by a distinctive ``magic angle”, $ \theta_M$ , where both the moiré unit cell and Brillouin zone collapse. Unlike conventional studies of moiré materials, which primarily focus on small lattice misalignments, we demonstrate that this moiré collapse occurs at large twist angles in generic twisted anisotropic homobilayers. The collapse angle, $ \theta_M$ , is likely to give rise quasi-crystal behavior as well as to the formation of strongly correlated states, that arise not from flat bands, but from the presence of ultra-anisotropic electronic states, where non-Fermi liquid phases can be stabilized. In this work, we develop a continuum model for electrons based on extensive \textit{ab initio} calculations for twisted bilayer black phosphorus, enabling a detailed study of the emerging moiré collapse features in this archetypal system. We show that the (temperature) stability criterion for the emergence of (sliding) Luttinger liquids is generally met as the twist angle approaches $ \theta_M$ . Furthermore, we explicitly formulate the collapsed single-particle one-dimensional (1D) continuum Hamiltonian and provide the \textit{fully interacting}, bosonized Hamiltonian applicable at low doping levels. Our analysis reveals a rich landscape of multichannel Luttinger liquids, potentially enhanced by valley degrees of freedom at large twist angles.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
Atomic layer etching of InGaAs using sequential exposures of atomic hydrogen and oxygen gas
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-25 20:00 EDT
Mete M. Bayrak, Anthony J. Ardizzi, Sadhvikas Addamane, Kieran Cleary, Austin J. Minnich
The high frequency performance and yield of III-V semiconductor devices such as InP HEMTs is negatively impacted by subsurface etch damage and non-uniform etch depth over the wafer. Atomic layer etching (ALE) has the potential to overcome this challenge because of its ability to etch with Angstrom-scale precision, low damage, and intrinsic wafer-scale uniformity. Here, we report an ALE process for InGaAs based on sequential atomic hydrogen and oxygen gas exposures. An etch rate of 0.095 Å/cycle was observed at 350 °C using ex-situ spectroscopic ellipsometry. The sample remains atomically smooth after 200 cycles of ALE. This process could be employed as a gate recess etch step in InP HEMT fabrication to improve microwave performance and yield.
Materials Science (cond-mat.mtrl-sci)
Fast readout of quantum dot spin qubits via Andreev spins
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-25 20:00 EDT
Michèle Jakob, Katharina Laubscher, Patrick Del Vecchio, Anasua Chatterjee, Valla Fatemi, Stefano Bosco
Spin qubits in semiconducting quantum dots are currently limited by slow readout processes, which are orders of magnitude slower than gate operations. In contrast, Andreev spin qubits benefit from fast measurement schemes enabled by the large resonator couplings of superconducting qubits but suffer from reduced coherence during qubit operations. Here, we propose fast and high-fidelity measurement protocols based on an electrically-tunable coupling between quantum dot and Andreev spin qubits. In realistic devices, this coupling can be made sufficiently strong to enable high-fidelity readout well below microseconds, potentially enabling mid-circuit measurements. Crucially, the electrical tunability of our coupler permits to switch it off during idle periods, minimizing crosstalk and measurement back-action. Our approach is fully compatible with germanium-based devices and paves the way for scalable quantum computing architectures by leveraging the advantages of heterogeneous qubit implementations.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
Self-assembled clusters of mutually repelling particles in confinement
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-25 20:00 EDT
P. D. S. de Lima, R. De La Cour, K. Gaff, J. M. de Araújo, S. J. Cox, M. S. Ferreira, S. Hutzler
Mutually repelling particles form spontaneously ordered clusters when forced into confinement. The clusters may adopt similar spatial arrangements even if the underlying particle interactions are contrastingly different. Here we demonstrate with both simulations and experiments that it is possible to induce particles of very different types to self-assemble into the same ordered geometric structure by simply regulating the ratio between the repulsion and confining forces. This is the case for both long- and short-ranged potentials. This property is initially explored in systems with two-dimensional (2D) circular symmetry and subsequently demonstrated to be valid throughout the transition to one-dimensional (1D) structures through continuous elliptical deformations of the confining field. We argue that this feature can be utilized to manipulate the spatial structure of confined particles, thereby paving the way for the design of clusters with specific functionalities.
Soft Condensed Matter (cond-mat.soft)
15 pages, 5 figures and 2 tables, submitted to PRE
Resonances of recurrence time of monitored quantum walks
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-25 20:00 EDT
Ruoyu Yin, Qingyuan Wang, Sabine Tornow, Eli Barkai
The recurrence time is the time a process first returns to its initial state. Using quantum walks on a graph, the recurrence time is defined through stroboscopic monitoring of the arrival of the particle to a node of the system. When the time interval between repeated measurements is tuned in such a way that eigenvalues of the unitary become degenerate, the mean recurrence time exhibits resonances. These resonances imply faster mean recurrence times, which were recorded on quantum computers. The resonance broadening is captured by a restart uncertainty relation [R. Yin, Q. Wang, S. Tornow, E. Barkai, Proc. Natl. Acad. Sci. U.S.A. 122, e2402912121 (2025)]. To ensure a comprehensive analysis, we extend our investigation to include the impact of system size on the widened resonances, showing how the connectivity and energy spectrum structure of a system influence the restart uncertainty relation. Breaking the symmetry of the system, for example time-reversal symmetry breaking with a magnetic flux applied to a ring, removes the degeneracy of {the eigenvalues of the unitary}, hence modifying {the mean recurrence time and the widening of the transitions}, and this effect is studied in detail. The width of resonances studied here is related to the finite time resolution of relevant experiments on quantum computers, and to the restart paradigm.19
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
19 pages, 11 figures. Accepted for publication in the Journal of Chemical Physics