CMP Journal 2025-08-14
Statistics
Nature Materials: 2
Nature Nanotechnology: 1
Science: 17
Physical Review Letters: 13
arXiv: 53
Nature Materials
Direct integration of optoelectronic arrays with arbitrary non-developable structures
Original Paper | Electronic devices | 2025-08-13 20:00 EDT
Meng Wang, Fengren Cao, Linxing Meng, Min Wang, Liang Li
The extension of optoelectronic devices from planar to non-developable structures has led to remarkable success in bionics, optical imaging and soft electronics. However, non-developable optoelectronic devices are achieved mainly via physical deformations and limited to a few geometries. Here we report a self-assembly perovskite strategy for integrating optoelectronic arrays with arbitrary non-developable structures. The perovskite films are grown from a rapid nucleation-dominated crystallization driven by the low energy fluctuation of lead iodide solution, where the fluid precursor can be evenly dispersed along non-developable substrates by surface tension and then self-assembles into compact films through gaseous manipulation. The strategy covers arbitrarily shaped substrates with three-dimensional length scales over 106 orders of magnitude and enables the unique structural manipulations of photodiode arrays with micrometre precision. As a proof of concept, the theoretical focal surface of a single-lens image system is realized into a non-developable sensor, effectively correcting the off-axis coma aberrations compared with its planar or hemispherical counterpart.
Electronic devices, Optoelectronic devices and components, Sensors and biosensors
Scalable photonic quantum technologies
Review Paper | Quantum information | 2025-08-13 20:00 EDT
Hui Wang, Timothy C. Ralph, Jelmer J. Renema, Chao-Yang Lu, Jian-Wei Pan
Photonic quantum technologies are now progressing from demonstrations of fundamental phenomena to systems of sufficient scale and quality to enable practical applications with quantum advantage in communications, computation and metrology. Here we review recent advances in quantum optics that have led to the emergence of such scalable quantum technologies, and outline the road ahead to more general applications with greater potential impact. We first focus on the components that support various photonic quantum applications, including quantum light sources, linear-optical networks and detectors. We go on to discuss recent experimental demonstrations of quantum communication, quantum computation and simulation, and quantum metrology using photons. Finally, an overview is provided on the manner in which photons fit within both the opportunities and challenges of implementing space-to-ground quantum internet, universal quantum computing and quantum precision measurement.
Quantum information, Quantum optics
Nature Nanotechnology
Efficient and tunable photochemical charge transfer via long-lived Bloch surface wave polaritons
Original Paper | Chemical physics | 2025-08-13 20:00 EDT
Kamyar Rashidi, Evripidis Michail, Bernardo Salcido-Santacruz, Yamuna Paudel, Vinod M. Menon, Matthew Y. Sfeir
Hybrid light-matter molecular exciton-polariton states have been proposed as a strategy to directly modify the efficiency and rate of photoinduced molecular charge transfer reactions. However, the efficacy of polariton-driven photochemistry remains an open question owing to the experimental challenges to tease out this effect. Here we demonstrate conditions under which photoinduced polaritonic charge transfer can be achieved and visualized using momentum-resolved ultrafast spectroscopy. Key conditions for charge transfer are satisfied using Bloch surface wave polaritons, which exhibit favourable dispersion characteristics that permit the selective pumping of hybrid states with long lifetimes (100-400 fs) that permit vibrationally assisted charge transfer between a donor and an acceptor molecule dispersed in a polymer matrix. Using this approach, we tune the energetic driving force for charge separation, reducing it by as much as 0.5 eV compared with the bare exciton pumping with an internal quantum efficiency of 0.77. These results corroborate the notion that tunable and efficient polariton-driven molecular charge transfer is indeed possible using carefully constructed photonic systems.
Chemical physics, Nanophotonics and plasmonics, Photochemistry, Polaritons
Science
Predicting fusion ignition at the National Ignition Facility with physics-informed deep learning
Research Article | Nuclear fusion | 2025-08-14 03:00 EDT
Brian K. Spears, Scott Brandon, Dan T. Casey, John E. Field, Jim A. Gaffney, Kelli D. Humbird, Andrea L. Kritcher, Michael K. G. Kruse, Eugene Kur, Bogdan Kustowski, S. Langer, Dave Munro, Ryan Nora, J. Luc Peterson, Dave J. Schlossberg, Paul Springer, Alex Zylstra
An inertial confinement fusion experiment, carried out at the National Ignition Facility, has achieved ignition by generating fusion energy exceeding the laser energy that drove the experiment. Prior to the experiment, a generative machine learning model that combines radiation hydrodynamics simulations, deep learning, experimental data, and Bayesian statistics was used to predict, with a probability greater than 70%, that ignition was the most likely outcome for this shot.
Observation of many-body dynamical localization
Research Article | Many-body dynamics | 2025-08-14 03:00 EDT
Yanliang Guo, Sudipta Dhar, Ang Yang, Zekai Chen, Hepeng Yao, Milena Horvath, Lei Ying, Manuele Landini, Hanns-Christoph Nägerl
The quantum kicked rotor is a paradigmatic model system in quantum physics. As a driven quantum system, it features dynamical localization, specifically Anderson localization in momentum space. However, the interacting many-body kicked rotor is believed to break localization. Here, we present evidence for many-body dynamical localization for the Lieb-Liniger version of the many-body quantum kicked rotor. After some initial evolution, the momentum distribution of interacting quantum-degenerate bosonic atoms in one-dimensional geometry, kicked hundreds of times by means of a pulsed sinusoidal potential, stops spreading. Our results shed light on the boundary between the classical, chaotic world and the realm of quantum physics.
Breast milk IgG engages the mouse neonatal immune system to instruct responses to gut antigens
Research Article | Immunology | 2025-08-14 03:00 EDT
Meera K. Shenoy, Diane M. Rico, Alina K. Lorant, Hamadoun Touré, Shannon Gordon, Luke J. Milburn, Jeanette S. Schwensen, Madelyn E. Cabán, Meghan A. Koch
Maternal antibodies fundamentally regulate gut immunity in the developing infant, yet the mechanisms underlying this process remain elusive. We found that maternal immunoglobulin G (IgG), ingested in the first week of life, restrained microbiota-dependent adaptive immune responses weeks later, after weaning. This activity was linked to maternal antibodies that could bind bacteria in the neonatal gut and the ability of microbe-IgG complexes to engage Fc and complement-dependent effector functions in offspring. Ingestion of microbiota-specific maternal IgG also limited aberrant neonatal responses to dietary antigens encountered at weaning. These discoveries suggest that maternal IgG engages the immune system of offspring in early postnatal life to tune mucosal responses and reinforce intestinal homeostasis in the face of dynamic shifts in food and bacterial antigens during development.
Platelets sequester extracellular DNA, capturing tumor-derived and free fetal DNA
Research Article | Platelets | 2025-08-14 03:00 EDT
Lauren Murphy, Jeanne Inchauspé, Giampiero Valenzano, Pamela Holland, Nikolaos Sousos, Hayley L. Belnoue-Davis, Rong Li, Natalie J. Jooss, Camelia Benlabiod, Eleanor Murphy, Zohar Etzioni, Emelie Shepherd, Lucy Denly, Sujata Biswas, Lin Chen, Jennifer O’Sullivan, Michael P. Rimmer, Abdullah O. Khan, Christina Simoglou Karali, Nadia Nasreddin, Ian S. Hitchcock, Milka Koupenova, Skirmantas Kriaucionis, Jim R. Hughes, Eric O’Neill, Manu Vatish, Paul Rees, Simon Leedham, Michael Desborough, Adam J. Mead, Benjamin Schuster-Böckler, Christopher D. Gregory, Bethan Psaila
Platelets are anucleate blood cells vital for hemostasis and immunity. During cell death and aberrant mitosis, nucleated cells release DNA, resulting in “cell-free” DNA in plasma (cfDNA). An excess of cfDNA is deleterious. Given their ability to internalize pathogen-derived nucleic acids, we hypothesized that platelets may also clear endogenous cfDNA. We found that, despite lacking a nucleus, platelets contained a repertoire of DNA fragments mapping across the nuclear genome. We detected fetal DNA in maternal platelets and cancer-derived DNA in platelets from patients with premalignant and cancerous lesions. As current liquid biopsy approaches utilize platelet-depleted plasma, important genetic information contained within platelets is being missed. This study establishes a physiological role for platelets that has not previously been highlighted, with broad translational relevance.
Cross-species implementation of an innate courtship behavior by manipulation of the sex-determinant gene
Research Article | Evolutionary biology | 2025-08-14 03:00 EDT
Ryoya Tanaka, Yusuke Hara, Kosei Sato, Soh Kohatsu, Hinata Murakami, Tomohiro Higuchi, Takeshi Awasaki, Shu Kondo, Atsushi Toyoda, Azusa Kamikouchi, Daisuke Yamamoto
In accepting a courting male, Drosophila subobscura females require nuptial gift giving in which a male gives regurgitated crop contents to her mouth to mouth. No similar behavior is found in D. melanogaster. By clonal activation of neurons expressing the male-determinant FruM, we identified insulin-like peptide-producing cells (IPCs) and their putative postsynaptic targets, proboscis-innervating motoneurons, as those critical for gift giving. We demonstrate that loss of FruM from D. subobscura IPCs abrogates neurite extension and gift giving, whereas FruM overexpression in their D. melanogaster counterparts induces overgrowth of neurites that harbor functional synapses, culminating in increased regurgitation. We suggest that the acquisition of FruM expression by IPCs was a key event occurring in an ancestral D. subobscura that conferred a latent capability to perform nuptial gift giving.
Mitochondria protect against an intracellular pathogen by restricting access to folate
Research Article | Cell biology | 2025-08-14 03:00 EDT
Tânia Catarina Medeiros, Jana Ovciarikova, Xianhe Li, Patrick Krueger, Tim Bartsch, Silvia Reato, John C. Crow, Michelle Tellez Sutterlin, Bruna Martins Garcia, Irina Rais, Kira Allmeroth, Matías D. Hartman, Martin S. Denzel, Martin Purrio, Andrea Mesaros, Kit-Yi Leung, Nicholas D. E. Greene, Lilach Sheiner, Patrick Giavalisco, Lena Pernas
As major consumers of cellular metabolites, mitochondria are poised to compete with invading microbes for the nutrients that they need to grow. Whether cells exploit mitochondrial metabolism to protect from infection is unclear. In this work, we found that the activating transcription factor 4 (ATF4) activates a mitochondrial defense based on the essential B vitamin folate. During infection of cultured mammalian cells with the intracellular pathogen Toxoplasma gondii, ATF4 increased mitochondrial DNA levels by driving the one-carbon metabolism processes that use folate in mitochondria. Triggered by host detection of mitochondrial stress induced by parasite effectors, ATF4 limited Toxoplasma access to folates required for deoxythymidine monophosphate synthesis, thereby restricting parasite growth. Thus, ATF4 rewires mitochondrial metabolism to mount a folate-based metabolic defense against Toxoplasma.
Artificial farnesol epoxidase enables a concise synthesis of meroterpenoids
Research Article | Biocatalysis | 2025-08-14 03:00 EDT
Jinxin Wang, Yunpeng Yin, Quan Zhang, Wei-Dong Zhang, Jian Li
Efficient asymmetric epoxidation reactions have been developed for both the head end and tail end double bonds of farnesol, greatly facilitating the synthesis of terpenoid natural products. However, the lack of methods for direct asymmetric epoxidation of the relatively inert internal alkene of farnesol has posed major challenges in the synthesis of many terpenoids. In this study, we describe the engineering of an epoxidase capable of selectively epoxidizing the internal alkene of farnesol with high regioselectivity and enantioselectivity. The resulting epoxidized intermediate has been successfully applied to simplify the synthesis of a variety of meroterpenoids, reducing the total number of synthetic steps by more than half in most cases.
Enantioconvergent benzylic C(sp3)‒N coupling with a copper-substituted nonheme enzyme
Research Article | Biocatalysis | 2025-08-14 03:00 EDT
Xuzhong Shen, Xiahe Chen, Yihang Xiao, Jesse B. Brown, James G. Zhang, Xinyuan Ji, Jinyan Rui, Marc Garcia-Borràs, Yi Rao, Yunfang Yang, Xiongyi Huang
Copper-catalyzed radical C(sp3)‒N coupling has become a major focus in synthetic catalysis over the past decade. However, achieving this reaction manifold by using enzymes has remained elusive. In this study, we introduce a photobiocatalytic approach for radical benzylic C(sp3)‒N coupling using a copper-substituted nonheme enzyme. Using rhodamine B as a photoredox catalyst, we identified a copper-substituted phenylalanine hydroxylase that facilitates enantioconvergent decarboxylative amination between N-hydroxyphthalimide esters and anilines. Directed evolution remodeled the active site, resulting in high enantioselectivities for most substrates. On the basis of molecular modeling and mechanistic studies, we propose that the enzyme accommodates a copper-anilide complex that reacts with a benzylic radical. This study expands the scope of non-natural biocatalytic transition metal catalysis to copper-catalyzed radical coupling.
Hierarchical chiral supramolecular assemblies with strong and invertible chiroptical properties
Research Article | Optical materials | 2025-08-14 03:00 EDT
Minju Kim, Mingyue Zhang, You-Liang Zhu, Yan Yan, Xin Pu, Woosung Choi, Sein Chung, Kilwon Cho, Jeongwon Kim, Vladimir Tsukruk, Zhenzhong Yang, Nicholas A. Kotov, Zhong-Yuan Lu, Dong Ha Kim, Zhiqun Lin
Supramolecular assemblies hold great promise for advanced chiral materials because of their structural diversity and dynamic features, but their low chiroptical activity limits practical applications. We report hierarchical supramolecular assemblies with giant chiroptical activity and mechanical attributes achieved through coassembly of achiral amphiphilic unimolecular micelles and chiral additives. Chiral fibrillar assemblies emerge from the nanostructured environment imposed by the micelles, driven by progressive chirality transfer through multiple hydrogen bonds between components. Integrating multifarious achiral luminescent molecules and nanocrystals into these assemblies leads to full-color circularly polarized luminescence-active materials with dissymmetry factors of ~10-1. A concentration-dependent chirality inversion is accessed through tailoring the coassembly kinetics. This strategy enables efficient red CPL, crucial for quantum and optical technologies.
Modulation of methyl-coenzyme M reductase expression alters the isotopic composition of microbial methane
Research Article | Methanogenesis | 2025-08-14 03:00 EDT
Jonathan Gropp, Markus Bill, Max K. Lloyd, Rebekah A. Stein, Dipti D. Nayak, Daniel A. Stolper
The stable isotopic composition of microbial methane varies substantially, and the underlying causes are debated. In this work, we experimentally controlled the abundance of the central enzyme in methanogenesis, methyl-coenzyme M reductase (MCR), in Methanosarcina acetivorans and tested whether its cellular concentration alters methane isotopic compositions. We found that during growth on methanol and acetate, lowering the expression of mcr increases the degree of hydrogen isotope exchange between methane and water. Using an isotope-enabled model of methanogenesis, we found that these changes result from an increase in reversibility of enzymes involved in the oxidation of the substrate methyl group. This result indicates that methane produced from organic compounds can deviate from commonly assumed pathway-specific isotope effects, with implications for the interpretation of environmentally relevant methane sources.
Directly observing replica symmetry breaking in a vector quantum-optical spin glass
Research Article | 2025-08-14 03:00 EDT
Ronen M. Kroeze, Brendan P. Marsh, David Atri Schuller, Henry S. Hunt, Alexander N. Bourzutschky, Michael Winer, Sarang Gopalakrishnan, Jonathan Keeling, Benjamin L. Lev
Spin glasses are quintessential examples of complex matter. Although their ordering lacks complete theoretical understanding, abstract models of spin glasses inform problems in other fields, such as combinatorial optimization and artificial intelligence–where they form a mathematical basis for neural network computing. We demonstrate the ability to realize a spin glass of a distinct driven-dissipative and vector form. By microscopically visualizing its glassy spin states, the technique allows us to directly measure replica symmetry breaking and the resulting ultrametric hierarchical structure. Ultrametricity is known to be emergent in models of evolution, protein folding, and climate change; this work shows it to be directly observable in a physically realized system.
Early germline sequestration in a basidiomycete fungus
Research Article | Fungal genetics | 2025-08-14 03:00 EDT
Markus Hiltunen Thorén, Boel Olsson, Peter Jan Vonk, Mattias Siljestam, Johan Reimegård, Martin Ryberg, Hanna Johannesson
In sexual organisms, inheritance of new mutations is highly dependent on the timing of germline definition. Here, we used the fairy ring-forming fungus Marasmius oreades to challenge the general assumption of a late germline separation in the Fungi. We collected mushrooms from different parts of rings over a 7-year period and identified new mutations in different tissues by whole-genome sequencing. We found evidence that fertile and sterile tissues had accumulated different mutations, suggesting that the germ line, destined for spore production, is already defined in the mycelium in this species. Moreover, the germ line carried fewer mutations than sterile tissues, indicating a lower mutation rate. Our findings suggest that early germline sequestration is more widespread than previously considered across multicellular life.
Linalool-triggered plant-soil feedback drives defense adaptation in dense maize plantings
Research Article | Plant communication | 2025-08-14 03:00 EDT
Dongsheng Guo, Zilin Liu, Jos M. Raaijmakers, Yachun Xu, Jinghui Yang, Matthias Erb, Jiabao Zhang, Yong-Guan Zhu, Jianming Xu, Lingfei Hu
High planting density boosts crop yields but also heightens pest and pathogen risks. How plants adapt their defenses under these conditions remains unclear. In this study, we reveal that maize enhances its defense in high-density conditions through a plant-soil feedback mechanism triggered by the leaf volatile linalool. Linalool activates jasmonate signaling in neighboring plants and promotes root exudation of benzoxazinoids, especially 2-(2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one)-β-d-glucopyranose (HDMBOA-Glc). These exudates in turn reshape the rhizosphere microbiome composition to favor growth of specific bacterial taxa that trigger broad-spectrum resistance, albeit at the cost of maize growth. This microbiome-driven feedback loop is governed by salicylic acid signaling. Our findings uncover intricate chemical signaling in high-density cropping, which is instrumental for improving soil health and designing sustainable strategies that balance the trade-off between plant growth and defense.
Scalable emulation of protein equilibrium ensembles with generative deep learning
Research Article | Protein simulations | 2025-08-14 03:00 EDT
Sarah Lewis, Tim Hempel, José Jiménez-Luna, Michael Gastegger, Yu Xie, Andrew Y. K. Foong, Victor García Satorras, Osama Abdin, Bastiaan S. Veeling, Iryna Zaporozhets, Yaoyi Chen, Soojung Yang, Adam E. Foster, Arne Schneuing, Jigyasa Nigam, Federico Barbero, Vincent Stimper, Andrew Campbell, Jason Yim, Marten Lienen, Yu Shi, Shuxin Zheng, Hannes Schulz, Usman Munir, Roberto Sordillo, Ryota Tomioka, Cecilia Clementi, Frank Noé
Following the sequence and structure revolutions, predicting functionally relevant protein structure changes at scale remains an outstanding challenge. We introduce BioEmu, a deep learning system that emulates protein equilibrium ensembles by generating thousands of statistically independent structures per hour on a single graphics processing unit (GPU). BioEmu integrates more than 200 milliseconds of molecular dynamics (MD) simulations, static structures, and experimental protein stabilities using new training algorithms. It captures diverse functional motions–including cryptic pocket formation, local unfolding, and domain rearrangements–and predicts relative free energies with 1 kilocalorie per mole accuracy compared with millisecond-scale MD and experimental data. BioEmu provides mechanistic insights by jointly modeling structural ensembles and thermodynamic properties. This approach amortizes the cost of MD and experimental data generation, demonstrating a scalable path toward understanding and designing protein function.
Integrated low-temperature PVC and polyolefin upgrading
Research Article | 2025-08-14 03:00 EDT
Wei Zhang, Boda Yang, Benjamin A. Jackson, Junbo Zhao, Honghong Shi, Donald M. Camaioni, Sungmin Kim, Huamin Wang, János Szanyi, Mal-Soon Lee, Jingguang G. Chen, Johannes A. Lercher
Polyolefins and their chlorinated derivatives (e.g., PVC) are among the most prevalent plastics in global production and waste streams. Traditional waste-to-energy methods, such as incineration and pyrolysis, as well as most chemical upcycling methods for PVC utilization, require thorough, high-temperature dechlorination to prevent the release of toxic chlorinated compounds. We present here a strategy for upgrading discarded PVC into chlorine-free fuel range hydrocarbons and HCl in a single-stage process, catalyzed by chloroaluminate ionic liquids. This approach offsets endothermic dechlorination and C-C bond cleavage with exothermic alkylation and hydrogen transfer by isobutane or isopentane in a low-temperature tandem process. The light isoalkanes are available from refinery processes and partly from recycling of the product stream. The process is suitable for handling real-world mixed and contaminated PVC and polyolefin waste streams.
Diffraction of helium and hydrogen atoms through single-layer graphene
Research Article | Structural methods | 2025-08-14 03:00 EDT
Carina Kanitz, Jakob Bühler, Vladimír Zobač, Joseph J. Robinson, Toma Susi, Maxime Debiossac, Christian Brand
Diffraction of atoms from surfaces provides detailed insights into structures, interactions, and dynamical processes. However, the method is currently limited to measurements in reflection–diffraction through materials has only been demonstrated for subatomic particles and is an outstanding challenge for atoms. In this work, we diffract helium and hydrogen atoms at kilo-electron volt energies through single-layer graphene at normal incidence. Despite the atoms’ high kinetic energy as well as coupling to the electronic system of graphene, we observe coherent scattering. This preservation of coherence was the result of the limited momentum transfer between the projectile and the lattice, resulting from interaction times on the femtosecond scale.
Solution-phase stabilization of a cyclocarbon by catenane formation
Research Article | Carbon allotropes | 2025-08-14 03:00 EDT
Yueze Gao, Prakhar Gupta, Igor Rončević, Coral Mycroft, Paul J. Gates, Anthony W. Parker, Harry L. Anderson
Cyclo[N]carbons, molecular rings consisting solely of N carbon atoms, have previously been studied in the gas phase and on surfaces at cryogenic temperatures, but they are generally considered too reactive to be studied under ambient laboratory conditions. In this study, we report the synthesis of a cyclo[48]carbon catenane, in which the C48 ring is protected by being threaded through three other macrocycles. This cyclo[48]carbon [4]catenane is stable enough for spectroscopic characterization in solution at room temperature. Its mass spectrum displays the expected molecular ions; its 13C nuclear magnetic resonance spectrum gives a single resonance for all 48 sp1 carbon atoms at 72.9 parts per million; and its Raman spectrum shows an intense peak at 1890 inverse centimeters, similar to linear polyynes.
Physical Review Letters
Full Characterization of Genuine 17-qubit Entanglement on the Superconducting Processor
Research article | Quantum tomography | 2025-08-13 06:00 EDT
Chang-Kang Hu, Yong Wang, YuXuan Zhou, ChiLong Liu, GuiXu Xie, RuiYang Zhou, HaoLan Yuan, Lijun Liu, Li Li, Song Liu, Dian Tan, Shuming Cheng, and Dapeng Yu
We present a least square state estimator regularized by state purity to accomplish the task of quantum state tomography and entanglement verification, and report an experimental validation on a superconducting processor. First, a scalable full-state tomography is achieved with state fidelity 0.8217(1) for the 9-qubit $W$ state and 0.6817(1) for the 17-qubit Greenberger-Horne-Zeilinger state, with the latter reaching 0.7587(1) under a pure-state assumption. Then, the presence of genuine multiqubit entanglement in the majority of generated states is conclusively certified by violating the corresponding entanglement witness. Finally, it is demonstrated that our method can achieve superior tomography accuracy with limited measurement settings and that mitigating error is essential for leveraging noisy quantum systems in quantum processing tasks. Our results pave the way for more accurate full characterization of larger-scale many-body quantum systems.
Phys. Rev. Lett. 135, 070801 (2025)
Quantum tomography
Constraints on Primordial Magnetic Fields from the Lyman-$\alpha $ Forest
Research article | Large scale structure of the Universe | 2025-08-13 06:00 EDT
Mak Pavičević, Vid Iršič, Matteo Viel, James S. Bolton, Martin G. Haehnelt, Sergio Martin-Alvarez, Ewald Puchwein, and Pranjal Ralegankar
We present the first constraints on primordial magnetic fields from the Lyman-$\alpha $ forest using full cosmological hydrodynamic simulations. At the scales and redshifts probed by the data, the flux power spectrum is extremely sensitive to the extra power induced by primordial magnetic fields in the linear matter power spectrum, at a scale that we parametrize with ${k}{\mathrm{peak}}$. We rely on a set of more than a quarter million flux models obtained by varying thermal and reionization histories and cosmological parameters. We find a hint of extra power that is well fitted by the primordial magnetic field model with $B\sim 0.2\text{ }\text{ }\mathrm{nG}$, corresponding to ${k}{\mathrm{peak}}\sim 20\text{ }\text{ }{\mathrm{Mpc}}^{- 1}$. However, when applying very conservative assumptions on the modeling of the noise, we obtain a $3\sigma $ C.L. lower limit ${k}{\mathrm{peak}}>30\text{ }\text{ }{\mathrm{Mpc}}^{- 1}$, which translates into the tightest bounds on the strength of primordial intergalactic magnetic fields: $B<0.30\text{ }\text{ }\mathrm{nG}$ (for a fixed, nearly scale-invariant ${n}{\mathrm{B}}=- 2.9$).
Phys. Rev. Lett. 135, 071001 (2025)
Large scale structure of the Universe, Primordial magnetic fields, Astrophysical & cosmological simulations
Probing Benchmark Models of Hidden-Sector Dark Matter with DAMIC-M
Research article | Particle astrophysics | 2025-08-13 06:00 EDT
K. Aggarwal et al. (DAMIC-M Collaboration)
We report on a search for sub-GeV dark matter (DM) particles interacting with electrons using the DAMIC-M prototype detector at the Modane Underground Laboratory. The data feature a significantly lower detector single ${e}^{- }$ rate (factor 50) compared to our previous search, while also accumulating a 10 times larger exposure of $\sim 1.3\text{ }\text{ }\mathrm{kg}\text{- }\mathrm{day}$. DM interactions in the skipper charge-coupled devices (CCDs) are searched for as groups of two or three adjacent pixels with a total charge between 2 and $4\text{ }\text{ }{e}^{- }$. We find 144 candidates of $2\text{ }\text{ }{e}^{- }$ and 1 candidate of $4\text{ }\text{ }{e}^{- }$, where 141.5 and 0.071, respectively, are expected from background. With no evidence of a DM signal, we place stringent constraints on DM particles with masses between 1 and $1000\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ interacting with electrons through an ultralight or heavy mediator. For large ranges of DM masses below $1\text{ }\mathrm{GeV}/{c}^{2}$, we exclude theoretically motivated benchmark scenarios where hidden-sector particles are produced as a major component of DM in the Universe through the freeze-in or freeze-out mechanisms.
Phys. Rev. Lett. 135, 071002 (2025)
Particle astrophysics, Particle dark matter, Hypothetical gauge bosons, Hypothetical scalars, Weakly interacting massive particles, Cosmic ray & astroparticle detectors, Dark matter detectors, Solid-state detectors
Evidence for Similar Collectivity of High Transverse-Momentum Particles in $p$-Pb and Pb-Pb Collisions
Research article | Collective flow | 2025-08-13 06:00 EDT
V. Chekhovsky et al. (CMS Collaboration)
Charged hadron elliptic anisotropies (${v}{2}$) are presented over a wide transverse momentum (${p}{\mathrm{T}}$) range for proton-lead ($p\mathrm{Pb}$) and lead-lead (PbPb) collisions at nucleon-nucleon center-of-mass energies of 8.16 and 5.02 TeV, respectively. The data were recorded by the CMS experiment and correspond to integrated luminosities of 186 and $0.607\text{ }\text{ }{\mathrm{nb}}^{- 1}$ for the $p\mathrm{Pb}$ and PbPb systems, respectively. A four-particle cumulant analysis is performed using subevents separated in pseudorapidity to effectively suppress noncollective effects. At high ${p}{\mathrm{T}}$ (${p}{\mathrm{T}}>8\text{ }\text{ }\mathrm{GeV}$), significant positive ${v}{2}$ values that are similar between $p\mathrm{Pb}$ and PbPb collisions at comparable charged particle multiplicities are observed. This observation suggests a common origin for the multiparticle collectivity for high-${p}{\mathrm{T}}$ particles in the two systems.
Phys. Rev. Lett. 135, 071903 (2025)
Collective flow, Quark-gluon plasma, Relativistic heavy-ion collisions, Hadron colliders
Low-Energy Constants of Chiral Perturbation Theory from Pion Scalar Form Factors in ${N}_{f}=2+1$-Flavor Lattice QCD with Controlled Errors
Research article | Chiral perturbation theory | 2025-08-13 06:00 EDT
Georg von Hippel and Konstantin Ottnad
We determine the low-energy constants ${f}{0}$, ${L}{4}^{r}$ and ${L}{5}^{r}$ of SU(3) chiral perturbation theory from a lattice QCD calculation of the scalar form factors of the pion with fully controlled systematics. Lattice results are computed on a large set of ${N}{f}=2+1$ gauge ensembles covering four lattice spacings $a\in [0.049,0.086]\text{ }\text{ }\mathrm{fm}$, pion masses ${M}{\pi }\in [130,350]\text{ }\text{ }\mathrm{MeV}$, and various large physical volumes. By determining the notorious quark-disconnected contributions with unprecedented precision and using a large range of source-sink separations ${t}{\mathrm{sep}}\in [1.0,3.25]\text{ }\text{ }\mathrm{fm}$, we are able for the first time to obtain the scalar radii from a $z$-expansion parametrization of the form factors rather than a simple linear approximation at small momentum transfer. The low-energy constants are obtained from the physical extrapolation of the radii using next-to-leading-order SU(3) next-to-leading-order chiral perturbation theory to parametrize the quark mass dependence. Systematic uncertainties are estimated via model averages based on the Akaike information criterion. Our determination of ${L}_{4}^{r}$ is the first lattice determination to obtain a result not compatible with zero.
Phys. Rev. Lett. 135, 071904 (2025)
Chiral perturbation theory, Pions, Form factors, Lattice QCD
Rapidity Asymmetry of Jet-Hadron Correlation as a Robust Signal of Diffusion Wake Induced by Dijets in High-Energy Heavy-Ion Collisions
Research article | Hard scattering | 2025-08-13 06:00 EDT
Zhong Yang and Xin-Nian Wang
Diffusion wake accompanying a Mach cone is a unique feature of the medium response to projectiles traveling at a speed faster than the velocity of sound. This is also the case for jet-medium interaction inside the quark-gluon plasma in high-energy heavy-ion collisions. It leads to a depletion of soft hadrons in the opposite direction of the propagating jet and, recently, has been observed in $Z$-jet events of $\mathrm{Pb}+\mathrm{Pb}$ collisions at LHC. In dijet events, however, the diffusion wake of one jet usually overlaps with the medium-induced hadron enhancement of the other jet without a clear signal except a reduction of the hadron enhancement, unless there is a large rapidity gap between the two jets. We propose to use the rapidity asymmetry of jet-hadron correlations in dijets with a finite rapidity gap relative to that without, as a robust and background-free signal of the diffusion wake. The asymmetry emerges because the diffusion wake of one jet is shifted to a finite rapidity relative to the other jet. Consequently, a depletion of soft hadrons appears in the shifted rapidity region of the diffusion wake and an enhancement in the rapidity region of the other jet whose soft hadron enhancement is no longer or less reduced by the diffusion wake as in dijets without a rapidity gap. We predict the rapidity asymmetry using both theoretical and mixed-event background subtraction for different values of the rapidity gap within the CoLBT-hydro model. Future measurements of this rapidity asymmetry with high statistics data on dijets should provide more precise insights into the jet-induced diffusion wake and properties of the quark-gluon plasma.
Phys. Rev. Lett. 135, 072302 (2025)
Hard scattering, Jet quenching, Particle correlations & fluctuations, Quark & gluon jets, Quark-gluon plasma, Transport in heavy-ion collisions
Group Delay Controlled by the Decoherence of a Single Artificial Atom
Research article | Quantum optics with artificial atoms | 2025-08-13 06:00 EDT
Y.-T. Cheng, K.-M. Hsieh, B.-Y. Wu, Z. Q. Niu, F. Aziz, Y.-H. Huang, P. Y. Wen, K.-T. Lin, Y.-H. Lin, J. C. Chen, A. F. Kockum, G.-D. Lin, Z.-R. Lin, Y. Lu, and I.-C. Hoi
The ability to slow down light at the single-photon level has applications in quantum information processing and other quantum technologies. We demonstrate two methods, both using just a single artificial atom, enabling dynamic control over microwave light velocities in waveguide quantum electrodynamics (QED). Our methods are based on two distinct mechanisms harnessing the balance between radiative decay and nonradiative decoherence rates of a superconducting artificial atom in front of a mirror. In the first method, we tune the radiative decay of the atom using interference effects due to the mirror; in the second method, we pump the atom to effectively control its nonradiative decoherence. When the half of the radiative decay rate exceeds the nonradiative decoherence rate, we observe positive group delay; conversely, dominance of the nonradiative decoherence results in negative group delay. Our results advance signal-processing capabilities in waveguide QED.
Phys. Rev. Lett. 135, 073601 (2025)
Quantum optics with artificial atoms, Superconducting qubits
Strong Coupling and Dark Modes in the Motion of a Pair of Levitated Nanoparticles
Research article | Optomechanics | 2025-08-13 06:00 EDT
A. Pontin, Q. Deplano, A. Ranfagni, F. Marino, and F. Marin
We experimentally investigate a system composed of two levitating nanospheres whose motions are indirectly coupled via coherent scattering in a single optical cavity mode. The nanospheres are loaded into a double longitudinal tweezer created with two lasers at different wavelengths, where chromatic aberration leads to the formation of two separate trapping sites. We achieve strong coupling between each pair of modes in the transverse plane of the tweezer, and we show the emergence of dark modes in the overall coupled motion. The observed features are ubiquitous in a variety of classical and quantum systems. As such, our experiment will allow us to explore the classical analog of typically quantum dynamics, and in further developments to investigate the transition to the quantum domain.
Phys. Rev. Lett. 135, 073602 (2025)
Optomechanics
Elastic Turbulence Hides in the Small Scales of Inertial Polymeric Turbulence
Research article | Turbulence | 2025-08-13 06:00 EDT
Piyush Garg and Marco Edoardo Rosti
Gaining a fundamental understanding of turbulent flows of dilute polymer solutions has been a challenging and outstanding problem for a long time. In this Letter, we examine homogeneous, isotropic polymeric turbulence at large Reynolds and Deborah numbers through direct numerical simulations. While at the largest scales at which the flow inertial turbulence exists, we find that the flow is fundamentally altered from Newtonian turbulence below the Kolmogorov scale. We demonstrate that ‘’elastic turbulence’’ exists at the smallest scales of polymeric turbulence by quantifying multiple statistical properties of the flow—energy spectrum and flux in Fourier space as well as the spatial statistics of the velocity field—the structure functions and kurtosis, and energy dissipation. Our results show the coexistence of two fundamentally distinct types of turbulence in polymeric fluids and point to the ubiquity of elastic turbulence, which was hitherto only known to exist for negligible inertia.
Phys. Rev. Lett. 135, 074001 (2025)
Turbulence, Turbulent multiphase flows, Complex fluids, Polymers
Excitonic Effects in Phonons: Reshaping the Graphene Kohn Anomalies and Lifetimes
Research article | Bethe-Salpeter equation | 2025-08-13 06:00 EDT
Alberto Guandalini, Francesco Macheda, Giovanni Caldarelli, and Francesco Mauri
We develop an ab initio framework that captures the impact of electron-electron and electron-hole interactions on phonon properties. This enables the inclusion of excitonic effects in the optical phonon dispersions and lifetimes of graphene, both near the center ($\mathrm{\Gamma }$) and at the border ($K$) of the Brillouin zone, at phonon-momenta relevant for Raman scattering and for the onset of the intrinsic electrical resistivity. Near $K$, we find a phonon redshift of $\sim 150\text{ }\text{ }{\mathrm{cm}}^{- 1}$ and a $10\times{}$ enhancement of the group velocity, together with a $5\times{}$ increase in linewidths due to a $26\times{}$ increase of the electron-phonon matrix elements. These effects persist for doping $2{E}{F}<\hbar {\omega }{\mathrm{ph}}$ and are quenched at higher dopings. Near $\mathrm{\Gamma }$, the excitonic effects are minor because of the gauge field nature of the electron-phonon coupling at small phonon momentum.
Phys. Rev. Lett. 135, 076401 (2025)
Bethe-Salpeter equation, Electron-phonon coupling, Electronic structure, Phonons, 2-dimensional systems, Graphene, Density functional calculations, Hybrid functionals, Tight-binding model
$1/5$ and $1/3$ Magnetization Plateaux in the Spin $1/2$ Chain System ${\mathrm{YbAlO}}_{3}$
Research article | Exotic phases of matter | 2025-08-13 06:00 EDT
P. Mokhtari, S. Galeski, U. Stockert, L. Behera, S. E. Nikitin, R. Wawrzyńczak, R. Küchler, M. Brando, L. Vasylechko, O. A. Starykh, and E. Hassinger
Quasi-one-dimensional magnets can host an ordered longitudinal spin-density wave state (LSDW) in magnetic field at low temperature, when longitudinal correlations are strengthened by Ising anisotropies. In the $S=1/2$ Heisenberg antiferromagnet ${\mathrm{YbAlO}}{3}$ this happens via Ising-like interchain interactions. Here, we report the first experimental observation of magnetization plateaux at $1/5$ and $1/3$ of the saturation value via thermal transport and magnetostriction measurements in ${\mathrm{YbAlO}}{3}$. We present a phenomenological theory of the plateau states that describes them as islands of commensurability within an otherwise incommensurate LSDW phase and explains their relative positions within the LSDW phase and their relative extent in a magnetic field. Notably, the plateaux are stabilized by ferromagnetic interchain interactions in ${\mathrm{YbAlO}}{3}$ and consistently are absent in other quasi-1D magnets such as ${\text{BaCo}}{2}{\mathrm{V}}{2}{\mathrm{O}}{8}$ with antiferromagnetic interchain interactions. We also report a small, steplike increase of the magnetostriction coefficient, indicating a weak phase transition of unknown origin in the high-field phase just below the saturation.
Phys. Rev. Lett. 135, 076704 (2025)
Exotic phases of matter, Magnetic interactions, Magnetic order, Magnetic phase transitions, Magnetic susceptibility, Magnetism, Order parameters, Phase diagrams, Phase transitions, Phasons, Spin density waves, Spin dynamics, Thermal conductivity
Harnessing Magnetic Octupole Hall Effect to Induce Torque in Altermagnets
Research article | Altermagnetism | 2025-08-13 06:00 EDT
Seungyun Han, Daegeun Jo, Insu Baek, Suik Cheon, Peter M. Oppeneer, and Hyun-Woo Lee
$d$-wave altermagnets have magnetic octupoles as their order parameters [S. Bhowal and N. A. Spaldin, Ferroically ordered magnetic octupoles in $d$-wave altermagnets, Phys. Rev. X 14, 011019 (2024)]. We theoretically show that magnetic octupoles injected from outside generate torque on the $d$-wave altermagnets. The injection can be achieved by the magnetic octupole Hall effect in an adjacent layer. We calculate the magnetic octupole Hall conductivity of the heavy metal $\alpha \text{- }\mathrm{W}$ and find a sizable value comparable to its spin Hall conductivity. Our work generalizes the spin Hall phenomenology (generation by heavy metals and detection by torque in ferromagnets) to the magnetic octupole Hall phenomenology (generation by heavy metals and detection by torque in altermagnets), which can be utilized to electrically control magnetic configurations of altermagnets.
Phys. Rev. Lett. 135, 076705 (2025)
Altermagnetism, Hall effect, Magnetism, Spintronics, Linear response theory
Erratum: Enhancement of Rydberg Blockade via Microwave Dressing [Phys. Rev. Lett. 134, 123404 (2025)]
Correction | | 2025-08-13 06:00 EDT
Deniz Kurdak, Patrick R. Banner, Yaxin Li, Sean R. Muleady, Alexey V. Gorshkov, S. L. Rolston, and J. V. Porto
Phys. Rev. Lett. 135, 079902 (2025)
arXiv
Thermal gradient effect on hydrogen transport in tungsten
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Sanad Alturk, Jacob Jeffries, Muhammed Kose, Enrique Martinez
One key challenge for efficiency and safety in fusion devices is the retention of tritium (T) in plasma-facing components. Tritium retention generates radioactive concerns and decreases the amount of fuel available to generate power. Hence, understanding the behavior of T in tungsten (W), as the main candidate as armor material, is critical to the deployment of fusion as a reliable energy source. In this work, we have studied the effect of a thermal gradient in the transport properties of hydrogen (as a T surrogate) in pure W. Strong thermal gradients develop in the divertor as a result of the intense energy fluxes arriving at the material. We have developed an analytical approach to compute the heat of transport ($ Q^\ast$ ) that is parameterized from molecular dynamics (MD) simulations. $ Q^\ast$ is a parameter needed in irreversible thermodynamics frameworks to understand mass transport in the presence of thermal gradients. We show that $ Q^\ast$ can be written as a function of temperature, temperature gradient, a characteristic length and the ratio of the rates towards hot and cold regions. Furthermore, we describe how, to first order, the dependence of $ Q^\ast$ on the thermal gradient vanishes, in agreement with MD results. On average, we find $ Q^\ast=-5.41\times 10^{-3}kT^2~\text{eV}$ for H in pure W, with $ k$ the Boltzmann constant and $ T$ the temperature.
Materials Science (cond-mat.mtrl-sci), Plasma Physics (physics.plasm-ph)
8 figures, 7 pages
Survival and Detection of Symmetry-Protected Topology in Loop Quenches
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Nicolò Forcellini, Miklós Horváth, Panagiotis Kotetes
We explore a class of dynamical protocols - that we term loop quenches - which are tailored for the study of symmetry-protected topological (SPT) systems. In loop quenches, SPT phases can survive even out of equilibrium, thus evading the dynamical violation of their protecting symmetry. Moreover, we demonstrate that employing loop quenches allows to detect the equilibrium topology via measurable dynamical quantities. Focusing on chiral-SPT phases, we introduce the Loschmidt chirality amplitude as a key observable that encodes the equilibrium topological invariant. We exemplify our method for chiral-symmetric one-dimensional two-band insulators and propose a pump-probe measurement scheme which allows to extract the amplitude in question. Our protocol uncovers a direct dynamical signature of SPT phases and, most importantly, paves the way for a general diagnostic framework that can be extended to other symmetry classes and dimensions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
6 pages, 3 figures
A microscopically reversible kinetic theory of flocking
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
We formulate a kinetic theory of two species of hard spheres which can undergo collisions converting chemical energy into kinetic energy. As the two species represent birds and air, this reactive collision mimics birds flapping their wings, allowing for their propulsion. We demand microscopic reversibility of the reactive collisions. We then introduce a chemostat to drive the system out of equilibrium. When the chemostat is sufficiently turned on and one restricts to grazing interspecies collisions, the momentum damping term can turn into a momentum growth term, hinting at a flocking transition.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
Numerically Discovered Inherent States are Always Protocol Dependent in Jammed Packings
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
Eddie Bautista, Eric I. Corwin
The energy landscape for soft sphere packings exists in a high-dimensional space and plays host to an astronomical number of local minima in a hierarchical and ultrametric arrangement. Each point in the landscape is a configuration that can be unambiguously mapped to its inherent state, defined as the local minimum that the configuration will flow to under perfectly overdamped continuous dynamics. Typically, discrete in time dynamics are used to computationally find local minima, but it is not known whether these algorithms are capable of reliably finding inherent states. Here, we use steepest descent dynamics to find the distribution of the largest time step, $ \delta_\textrm{best}$ , which finds the inherent state. We find that for systems of $ N$ particles, $ \delta_\textrm{best}$ is approximately proportional to $ N^{-3}$ , and weakly dependent on d and $ \varphi$ . We argue that the proportionality is due to saddle points in the energy landscape. Our results suggest that it is impossible, in practice, to reliably find inherent states for systems of about 64 particles or more.
Soft Condensed Matter (cond-mat.soft)
5 pages, 3 figures
Rigidity paradox of kirigami arches
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
The geometry of bending-active kirigami arches, decorated by cuts and holes, is strongly influenced by the location and geometry of the perforations. This study demonstrates that, in some instances, the geometric stiffening induced by additional cuts can outweigh the weakening effect of material removal, leading to a counterintuitive increase in structural rigidity under a given concentrated load. We present multiple parametric cut patterns to show that rigidity can be increased both under symmetric and asymmetric loads. While the preferred cut location is often near the point of action of the load, asymmetric loading can shift this optimum elsewhere. Moreover, the distance between the supports also plays a crucial role, namely, the rigidity gain vanishes when the supports are too far apart. We found that the rigidity can be increased for both non-perforated and perforated sheets, and there is a non-monotonic relationship between the global porosity and the rigidity of the structure. Numerical predictions are validated against experimental measurements.
Soft Condensed Matter (cond-mat.soft)
24 pages, 17 figures
Orbital dependent Coulomb drag in electron-hole bilayer graphene heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Zuocheng Zhang, Ruishi Qi, Jingxu Xie, Qize Li, Takashi Taniguchi, Kenji Watanabe, Michael F. Crommie, Feng Wang
We report Coulomb drag studies in an electron-hole bilayer graphene heterostructure in a magnetic field, where the orbital, spin, and valley degrees of freedom are lifted by the combined effects of exchange interaction, Zeeman energy, and vertical displacement field. Our device enables the application of a large vertical displacement field in both layers. In addition to the well-established strong Coulomb drag between Landau levels with an orbital quantum number N = 0, we observe a Coulomb drag signal between the N = 1 Landau levels under a suitable vertical displacement field. As the displacement field increases further, the Coulomb drag signal between N = 1 Landau levels weakens, and a Coulomb drag signal emerges between the N = 0 and N = 1 Landau levels. These findings suggest the important roles of the orbital index and vertical displacement field in interlayer Coulomb interactions within the quantum Hall regime of coupled bilayer systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Controlled Growth of Bronze Telluride for Scalable Thermoelectric Energy Harvesting
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Karthik R, Abhijith MB, Juan Gomez Quispe, Varinder Pal, Manas Paliwal, Ajit K Roy, Pedro Alves Da Silva Autreto, Sreeram Punathil Raman, Pulickel M. Ajayan, Chandra Sekhar Tiwary
With the growing demand for sustainable and decentralized energy solutions, thermoelectric energy harvesting has emerged as a promising technology for directly converting waste heat into electricity through solid state, environmentally friendly means. Among copper chalcogenides, Cu2Te is a notable p-type material due to its degenerate semiconducting nature and low thermal conductivity. In this study, we present a sustainable synthesis strategy for Sn-doped Cu2Te referred to as bronze telluride (BT) via a chemical vapor deposition (CVD) assisted tellurization process using pre-alloyed Cu Sn (bronze) powder. The resulting BT exhibited an enhanced thermoelectric figure of merit (ZT) of 1 at 500 K. To assess practical applicability, BT was integrated with n type galena (PbS) in a cascaded p n thermoelectric module, which generated 2.8 mV across a temperature gradient of 35 K, demonstrating its potential for medium- to high-temperature waste heat recovery. Furthermore, thermodynamic calculations and density functional theory (DFT) simulations provided insights into the formation mechanism of Cu2Te and the thermoelectric behaviour of BT. This work introduces an efficient, scalable, and environmentally responsible pathway for developing copper-based thermoelectric materials using industrially relevant precursors.
Materials Science (cond-mat.mtrl-sci)
17 pages, 6 figures
Dimensional analysis for clogging of grains in two and three dimensions
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
Julián Montero, Ryan Kozlowski, Luis A. Pugnaloni
We conduct standard dimensional analysis (Vaschy–Buckingham $ \Pi$ -theorem) for the mean avalanche size $ \langle s \rangle$ when particles flow through, and clog at, a small orifice on the base of a flat-bottomed silo. We consider the effect of particle diameter $ d$ , orifice diameter $ D$ , particle density $ \rho$ , particle Young’s modulus $ E$ and acceleration of gravity $ g$ . We both perform discrete element method simulations and compile available data in the literature in order to sample the parameter space. We find that our simulations and data across many experiments and simulations of frictional grains are consistent with the scaling equation $ \ln (\langle s \rangle+1) = A_\alpha (D/d-1)^{\alpha} + B_\alpha \sqrt{\rho g d / E}$ , where $ A_\alpha$ and $ B_\alpha$ are empirical constants and $ \alpha$ is the dimensionality of the system ($ \alpha=2$ and $ \alpha=3$ for 2D and 3D, respectively). This expression successfully synthesizes the clogging behavior of a number of related clogging systems and motivates future extensions to more complex configurations involving, for example, very low friction particles or external vibrations.
Soft Condensed Matter (cond-mat.soft)
Antiferron Modes in Ferroelectric Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
David Galvez-Poblete, Mario A. Castro, Roberto E. Troncoso, Guillermo Romero, Alvaro S. Nunez, Sebastian Allende
We introduce the concept of antiferron modes in ferroelectric materials as dynamically stabilized collective excitations over inverted polarization states that decrease the system energy. While ferrons represent quantized oscillations around the stable polarization minimum, antiferrons require dynamic stabilization via high-frequency driving. Using a generalized Landau-Ginzburg-Devonshire framework, we derive the effective curvature corrections from external driving, demonstrate the conditions for stabilizing metastable wells, and present the quantized Hamiltonian. Antiferrons could be a promising candidate for developing electrical sensing devices, offering tunable, dynamically controllable excitations with high sensitivity to external electric fields.
Materials Science (cond-mat.mtrl-sci)
Exploring the Nonlinear Rheology of Composite Hydrogels: A New Paradigm for LAOS Analysis
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
Wayan A. Fontaine-Seiler, Gavin J. Donley, Emanuela Del Gado, Daniel L. Blair
We investigate composite biopolymer networks composed of co-polymerized fibrin and gelatin networks and perform rheological measurements over a broad parameter space including strain amplitudes that go beyond the linear response regime. One goal of the work presented here is to provide a prototypical biocomposite material with highly separable polymerization times and controlled nonlinear rheological characteristics. We then extend the Sequence of Physical Processes (SPP)\cite{Rogers2017} into a statistical and geometrical framework that fingerprints the nonlinear rheological response of biopolymer composite gels. Our analysis is based on the changes in the shape of the time-dependent Cole-Cole plots that allow to reduce the time resolved analysis of the SPP method into the transition between linear and nonlinear behavior as the rheological parameters are varied. While the results clearly highlight how the mechanical responses of individual constituents are not simply additive, our extended SPP analysis provides a robust and intuitive classification scheme for comparing the nonlinear response of composite materials subjected to large oscillatory strain.
Soft Condensed Matter (cond-mat.soft)
Electric-Field Control of Josephson Oscillations in Dipolar Bose-Einstein Condensates
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-14 20:00 EDT
David Galvez-Poblete, Roberto E. Troncoso, Guillermo Romero, Alvaro S. Nunez, Sebastian Allende
We study the dynamic behavior of a Bose-Einstein condensate (BEC) with dipolar interactions when the influence of external electric fields affects the coherent tunneling properties. Here, we propose a tunable platform based on BECs where Josephson oscillations can be engineered and modulated through external electric fields. We develop a theoretical and numerical frame-work that reveals how electric fields affect intercondensate tunneling, phase dynamics, and collective excitations. By employing a coupled set of Gross-Pitaevskii equations with adiabatic elimination of excited states, we demonstrate field-induced tuning of Josephson frequencies and a transition from contact to dipole-dominated regimes. These findings corroborate theoretical predictions about the sensitivity of dipolar BECs to external fields and deepen our understanding of quantum coherence and tunneling in long-range interacting quantum systems.
Quantum Gases (cond-mat.quant-gas)
Trigonal warping enables linear optical spectroscopy in single-valley superconductors
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-14 20:00 EDT
Benjamin A. Levitan, Étienne Lantagne-Hurtubise
In superconductors with multiple pairing channels, Bardasis-Schrieffer modes and clapping modes arise as fluctuations in channels whose angular momenta differ from that of the pair condensate. Crystal symmetries often impose selection rules which keep these modes optically dark. We show that if pairing occurs around a single Fermi surface, trigonal warping renders both of these modes, as well as the quasiparticle excitation gap, visible in the longitudinal and Hall optical responses. Our results suggest that rhombohedral graphene multilayers, which are believe to host the required ingredients, might offer an ideal setting for the study of exotic superconducting collective modes.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
Main text is 4 pages with 1 figure
Bose-Einstein condensate sub-wavelength confinement via superoscillations
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-14 20:00 EDT
Dusty R. Lindberg, Gerard McCaul, Peisong Peng, Lev Kaplan, Diyar Talbayev, Denys I. Bondar
Optical lattices are essential tools in ultra-cold atomic physics. Here we demonstrate theoretically that sub-wavelength confinement can be achieved in these lattices through \textit{superoscillations}. This generic wave phenomenon occurs when a local region of the wave oscillates faster than any of the frequencies in its global Fourier decomposition. To illustrate how sub-wavelength confinement can be achieved via superoscillations, we consider a one-dimensional tri-chromatic optical potential confining a spinless Bose-Einstein Condensate of $ ^{87}$ Rb atoms. By numerical optimization of the relative phases and amplitudes of the optical trap’s frequency components, it is possible to generate superoscillatory spatial regions. Such regions contain multiple density peaks at sub-wavelength spacing. This work establishes superoscillations as a viable route to sub-wavelength BEC confinement in blue-detuned optical lattices.
Quantum Gases (cond-mat.quant-gas), Optics (physics.optics), Quantum Physics (quant-ph)
Energetically Favored One-Dimensional Moiré Superstructure in the Pseudo-Square Lattice GdTe3
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Jieun Yeon, Kihyun Lee, Myeongjin Jang, Tae Keun Yun, Jongho Park, Changyoung Kim, Kwanpyo Kim
Moiré engineering in layered crystals has recently gained considerable attention due to the discovery of various structural and physical phenomena, including interfacial reconstruction, superconductivity, magnetism, and distinctive optoelectronic properties. Nevertheless, most explored moiré systems have been limited to hexagonal lattices, thereby constraining a comprehensive understanding and technological application of moiré phenomena in general layered crystals. Here, we investigate GdTe3, a pseudo-tetragonal layered crystal, as a platform to explore unconventional moiré phenomena. GdTe3 exhibits a slight in-plane distortion correlated with the direction of charge density wave formation. Through vertical stacking of layers with different distortions-induced via a controlled strain/release process-we realize energetically favorable one-dimensional (1D) moiré superstructures. Using transmission electron microscopy (TEM), including high-resolution scanning TEM imaging, dark-field TEM imaging, and sample tilting experiments, we systematically examine stacking variations across the 1D moiré structure. Additionally, electron energy loss spectroscopy reveals modulations in electronic properties associated with the 1D moiré structure. Our findings expand the scope of moiré systems beyond conventional hexagonal twistronics, enabling exploration of moiré phenomena in low-symmetry van der Waals crystals.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
24 pages, 5 figures
ACS Nano (2025)
Ultrafast Optical Evidence of Split Density Waves in Bilayer Nickelate La$_3$Ni$_2$O$_7$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-14 20:00 EDT
Qi-Yi Wu, De-Yuan Hu, Chen Zhang, Mengwu Huo, Hao Liu, Bo Chen, Ying Zhou, Zhong-Tuo Fu, Chun-Hui Lv, Zi-Jie Xu, Hai-Long Deng, H. Y. Liu, Jun Liu, Yu-Xia Duan, Meng Wang, Jian-Qiao Meng
Utilizing ultrafast optical pump-probe spectroscopy, we investigated the quasiparticle and spin dynamics in single crystals of bilayer nickelate La$ _3$ Ni$ _2$ O$ 7$ . Our experimental results unequivocally demonstrate the presence of two distinct density wave (DW)-like orders, manifesting with onset temperatures at $ \sim$ 140 K and $ \sim$ 115 K. Through time-resolved ellipticity measurements, we identified the higher-temperature order at 140 K ($ T{\rm SDW}$ ) as the onset of a spin density wave (SDW) with associated electronic nematicity. In contrast, the lower-temperature order is attributed to a charge order. A key finding is the differential response of these orders to photoexcitation: the charge order is entirely suppressed at a pump fluence of approximately 40 $ \mu$ J/cm$ ^2$ , whereas the SDW order persists up to 200 $ \mu$ J/cm$ ^2$ , albeit with its characteristic temperature suppressed to approximately 70 K. These compelling experimental observations provide critical insights into the coexistence and manipulability of density wave phenomena in La$ _3$ Ni$ _2$ O$ _7$ , laying a foundation for future research into their optical control.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
7 pages, 4 figures. Any comment is welcome
Giant Shift Current in Electrically-Tunable Superlattice Bilayer Graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Nabil Atlam, Swati Chaudhary, Arpit Raj, Matthew Matzelle, Barun Ghosh, Gregory Fiete, Arun Bansil
Recent introduction of superlattice potentials has opened new avenues for engineering tunable electronic band structures featuring topologically nontrivial moiré-like bands. Here we consider optoelectronic properties of Bernal-stacked graphene subjected to a superlattice potential either electrostatically or through lattice twisting to show that it exhibits a giant shift current response that is orders of magnitude larger than existing predictions in twisted mulitlayer systems. Effects of gate voltage and the strength and phase of the superlattice potential on the shift current are delineated systematically across various topological regimes. Our study gives insight into the nature of nonlinear responses of materials and how these responses could be optimized by tuning the superlattice potential.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Planar Hall effects in $X$-wave magnets with $X=p,d,g,f,i$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
The planar Hall effect is a phenomenon that the Hall conductivity emerges perpendicular to the electric field in the presence of an in-plane magnetic field. We investigate the planar Hall effect in two-dimensional higher symmetric $ X$ -wave magnets with $ X=p,d,f,g,i$ , where those with $ X=d,g,i$ are altermagnets. The $ X$ -wave magnet is characterized by the number $ N_{X}$ of the nodes in the band structure, where $ N_{X}=1,2,3,4,6$ corresponding to $ X=p,d,f,g,i$ . We demonstrate that the Hall conductivities are almost half quantized and well approximated by the formula $ \sigma {xy}=\pm (e^{2}/2h)$ sgn$ \left( J\sin N{X}\Phi \right) $ , where $ J$ is the coefficient of the coupling between the $ X$ -wave magnet and the electrons, and $ \Phi $ is the direction of the applied magnetic field. Hence, the Hall conductivity has the periodicity with respect to $ \Phi $ , and the periodicity is equal to the number $ N_{X}$ of the nodes. This property may be used to confirm that the target material is indeed an $ X$ -wave magnet. Furthermore, the sign of $ J$ may be used as a bit for antiferromagnetic spintronics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages, 8 figures
Entropy of a double quantum dot
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
David Kealhofer, Christoph Adam, Max J. Ruckriegel, Petar Tomić, Benedikt Kratochwil, Christian Reichl, Yigal Meir, Werner Wegscheider, Thomas Ihn, Klaus Ensslin
We use charge sensing to detect entropy changes in a double quantum dot defined by electrostatic gating of a GaAs/AlGaAs heterostructure. This system can be tuned to be two separate systems, like two independent, artificial atoms, or a single coherent system, like a molecule. We study entropy changes in both regimes due to changes in the occupation of the system. First we recover the single-dot result for each dot, that the occupation of the dot by a single electron corresponds to an increase in the entropy of $ k_{\mathrm{B}} \log 2$ . Next we examine two different charge transitions in the “molecular” regime, and how it reveals itself in terms of the measured entropy. We also uncover a realization of Pauli blockade that clutters the entropy signal. By applying a rate equation model, we demonstrate the effect’s nonequilibrium origins and exclude it from the analysis of the system’s entropy. Understanding these experiments in this simplest coupled system enables the study of the entropy in other, more complicated coupled quantum systems, such as ones with topological or highly entangled ground states.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Main text 5 pages, 3 figures + supplementary 12 pages, 11 figures
Pressure in active matter
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
Guo Yu, Ruiyao Li, Fukang Li, Jiayu Zhang, Xiyue Li, Zequ Chen, Joscha Mecke, Yongxiang Gao
In the last decade, the study of pressure in active matter has attracted growing attention due to its fundamental relevance to nonequilibrium statistical physics. Active matter systems are composed of particles that consume energy to sustain persistent motion, which are inherently far from equilibrium. These particles can exhibit complex behaviors, including motility-induced phase separation, density-dependent clustering, and anomalous stress distributions, motivating the introduction of active swim stress and swim pressure. Unlike in passive fluids, pressure in active systems emerges from momentum flux originated from swim force rather than equilibrium conservative interactions, offering a distinct perspective for understanding their mechanical response. Simple models of active Brownian particles (ABPs) have been employed in theoretical and simulation studies across both dilute and dense regimes, revealing that pressure is a state function and exhibits a nontrivial dependence on density. Together with nonequilibrium statistical concepts such as effective temperature and effective adhesion, pressure offers important insight for understanding behaviors in active matter such as sedimentation equilibrium and motility induced phase separation. Extensions of ABPs models beyond their simplest form have underscored the fragility of pressure-based equation of state, which can break down under factors such as density-dependent velocity, torque, complex boundary geometries and interactions. Building on these developments, this review provides a comprehensive survey of theoretical and experimental advances, with particular emphasis on the microscopic origins of active pressure and the mechanisms underlying the breakdown of the equation of state.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
17 pages, 10 figures
Mechanical Force-Driven Charge Redistribution for Hydrogen Release at Ambient Conditions in Transition Metal-Intercalated Bilayer Graphene
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Jongdeok Kim, Vikram Mahamiya, Massimiliano Di Ventra, Hoonkyung Lee
Transition-metal (TM) atom-functionalized nanomaterials are promising candidates for hydrogen storage due to their ability to adsorb multiple hydrogen molecules through Kubas interactions. However, achieving efficient hydrogen desorption at ambient conditions remains a critical challenge for practical use. Here, we present a novel approach to modulate the desorption temperature of hydrogen in TM-intercalated bilayer graphene (BLG) using external mechanical forces. By employing first-principles density functional theory (DFT) and thermodynamic occupancy probability calculations, we demonstrate that adjusting the interlayer distance allows for precise control over the interaction energy of H2, thereby facilitating its desorption at ambient conditions. Complete hydrogen desorption occurs when the interlayer distance is reduced below 4.7 Å, 5.3 Å, and 5.1 Å for Sc-, Ti-, and V-intercalated BLG, respectively. Our findings suggest that external mechanical forces can effectively bring hydrogen occupancy to zero by minimizing charge transfer from the TM d-orbitals to H2 antibonding orbitals. Notably, while the total charge transferred from the TM atoms remains nearly constant at varying interlayer distances, its redistribution between the graphene layers and H2 fine-tunes the interaction strength. This approach can be extended to large interlayer distances, as supported by recent experiments on graphene oxide membranes [ACS Nano 12, 9309 (2018)]. Furthermore, recent experimental advances in noble gas and alkali metal intercalation in BLG highlight the potential of this approach to overcome the long-standing challenge of high desorption temperatures in TM-functionalized layered nanomaterials.
Materials Science (cond-mat.mtrl-sci)
23 pages, 8 figures
Boron Clusters for Metal-Free Water Splitting
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Masaya Fujioka, Haruhiko Morito, Melbert Jeem, Jeevan Kumar Padarti, Kazuki Morita, Taizo Shibuya, Masashi Tanaka, Yoshihiko Ihara, Shigeto Hirai
Electron-deficient boron clusters are identified as a fundamentally new class of oxygen evolution reaction (OER) catalysts, entirely free of transition metals. Selective sodium extraction from NaAlB14 and Na2B29 via high-pressure diffusion control introduces hole doping into B12 icosahedral frameworks, resulting in OER activity exceeding that of Co3O4 by more than an order of magnitude, and exceptional durability under alkaline conditions. B12 clusters are known for their superchaotropic character, which destabilizes hydrogen bonding in water. In this system, H2O, instead of OH-, preferentially adsorbs on the catalyst surface, suggesting a distinct OER pathway mediated by molecular water. This adsorption behavior contrasts with conventional transition-metal oxides and reflects the unique interfacial properties of the boron clusters. Density functional theory reveals unoccupied p orbitals and unique local electric fields at the cluster surface, both of which could promote the water activation. These findings suggest a paradigm shift in OER catalysis, in which the unique interaction between B12 clusters and water drives the reaction, replacing the conventional role of redox-active metals. Hole-doped boron clusters thus offer a promising platform for designing high-performance and durable water-splitting catalysts, opening new avenues for OER design beyond conventional transition-metal chemistry.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
22 pages, 6 figures
Discovery and Synthesis of a Family of Boride Altermagnets
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Zhen Zhang, Eranga H. Gamage, Genevieve Amobi, Subhadip Pradhan, Andrey Kutepov, Kirill D. Belashchenko, Yang Sun, Kirill Kovnir, Vladimir Antropov
Borides are a rich material family. To push the boundaries of borides’ properties and applications into broader fields, we have conducted systematic theoretical and experimental searches for synthesizable phases in ternary borides TM$ _2$ B$ _2$ (T = 3d, M = 4d/5d transition metals). We find that TM$ _2$ B$ _2$ in the FeMo$ _2$ B$ _2$ -type and CoW$ _2$ B$ _2$ -type structures form a large family of stable/metastable materials of 120 members. Among them, we identify 40 materials with stable magnetic solutions. Further, we discover 11 altermagnets in the FeMo$ _2$ B$ _2$ -type structure. So far, boride altermagnets are rare. In these altermagnets, T = Fe or Mn atoms are arranged in parallel T-chains with strong ferromagnetic intrachain couplings and antiferromagnetic interchain couplings. They simultaneously exhibit electronic band spin splitting, typical of ferromagnetism, and zero net magnetization, typical of antiferromagnetism. They also exhibit magnonic band chiral splitting. Both effects originate from the unique altermagnetic symmetries crucially constrained by the nonmagnetic atoms in the structure. Transport properties of relevance to spintronic applications, including the strain-induced spin-splitter effect and anomalous Hall effect, are predicted. An iodine-assisted synthesis method for TM$ _2$ B$ _2$ is developed, using which 7 of the predicted low-energy phases are experimentally synthesized and characterized, including 4 altermagnets. This work expands the realm of borides by offering new opportunities for studying altermagnetism and altermagnons in borides. It also provides valuable insights into the discovery and design of altermagnets. By demonstrating that altermagnets can exist as families sharing a common motif, this work paves a feasible route for discovering altermagnets by elemental substitutions and high-throughput computations.
Materials Science (cond-mat.mtrl-sci)
Twist-angle tunable Josephson junctions in three-dimensional superconductors
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Tenta Tani, Takuto Kawakami, Mikito Koshino
We theoretically investigate the superconducting phase and perpendicular Josephson supercurrent in twisted three-dimensional (3D) superconductors, where two layered 3D materials are stacked with a relative twist. We formulate the Bogoliubov-de Gennes Hamiltonian and develop a self-consistent method to calculate the superconducting order parameter and the resulting supercurrent. Applying this framework to a toy model with Fermi surfaces located near the Brillouin zone corners, we demonstrate a phase discontinuity at the twisted interface, indicating that a Josephson junction is formed purely by the twist. Our calculations reveal that the interface supports a finite critical current even when the Fermi surfaces of the two superconductors are completely separated, unlike in the case of a twisted normal-metal interface. We further show that the critical current can be effectively controlled by the twist angle, transitioning from a high-transparency regime at small angles to a low-transparency regime at larger angles.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
15 pages, 11 figures
Phonon interference effects in GaAs-GaP superlattice nanowires
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Chaitanya Arya, Johannes Trautvetter, Jose M. Sojo-Gordillo, Yashpreet Kaur, Valentina Zannier, Fabio Beltram, Tommaso Albrigi, Alicia Ruiz-Caridad, Lucia Sorba, Riccardo Rurali, Ilaria Zardo
Fine-tuning the functional properties of nanomaterials is crucial for technological applications. Superlattices, characterized by periodic repetitions of two or more materials in different dimensions, have emerged as a promising area of investigation. We present a study of the phonon interference effect on thermal transport in GaAs-GaP superlattice nanowires with sharp interfaces between the GaAs and GaP layers, as confirmed by high-resolution transmission electron microscopy. We performed thermal conductivity measurements using the so-called thermal bridge method on superlattice nanowires with a period varying from 4.8 to 23.3 nm. The measurements showed a minimum of the thermal conductivity as a function of superlattice period up to room temperature, that we interpreted as an indication of the crossover from coherent to incoherent thermal transport. Notably, this effect is not destroyed by surface boundary or by phonon-phonon scattering, as the crossover trend is also observed at room temperature. Our results were corroborated by both ab initio lattice dynamics and semiclassical nonequilibrium molecular dynamics calculations. These findings provide insights into the wave-like and particle-like transport of phonons in superlattice nanowires and demonstrate the potential for engineering thermal properties through precise control of the superlattice structure.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
Main article: 22 pages, 4 figures, 41 references. Supplementary: 16 pages, 6 figures, 19 references
Investigating oxides by electrochemical projection of the oxygen off-stoichiometry diagram onto a single sample
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Alexander Stangl (1, 2), Alexander Schmid (3), Adeel Riaz (1), Martin Krammer (3), Andreas Nenning (3), Fjorelo Buzi (4), Fabrice Wilhelm (5), Francesco Chiabrera (4), Federico Baiutti (4), Albert Tarancón (4, 6), Juergen Fleig (3), Arnaud Badel (7), Mónica Burriel (1) ((1) Univ. Grenoble Alpes, CNRS, Grenoble INP, LMGP, Grenoble, France, (2) Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble, France, (3) Institute of Chemical Technologies, Analytics, TU Wien, Vienna, Austria, (4) Catalonia Institute for Energy Research (IREC), Barcelona, Spain, (5) European Synchrotron Radiation Facility (ESRF), Grenoble, France, (6) ICREA, Barcelona, Spain, (7) Univ. Grenoble Alpes, CNRS, Grenoble INP, G2ELab - Institut Néel, Grenoble, France)
The oxygen stoichiometry is an essential key to tune functional properties of advanced oxide materials and thus has motivated numerous studies of the oxygen off-stoichiometry diagram, with the aim to determine and control structural, electronic, ionic, electrochemical and optical properties, as well as thermodynamic quantities such as the oxygen storage capacity, among others. Here, a novel approach is developed, which allows to project a broad range of oxygen chemical potentials onto a single thin film sample with unprecedented control via electrochemical polarization. Therefore, a specifically designed electrochemical cell geometry is deployed, resulting in a well-defined, linear, 1D in-plane oxygen concentration gradient, independent of variations in the materials electrical resistivity, whose endpoints can be flexibly controlled via the external pO2 and applied overpotential. This allows for an unparalleled study of materials properties as a continuous function of the oxygen content using spatially resolved tools (spectroscopic, diffraction, microscopy, local electrical probes, etc.) and thereby greatly reduces experimental efforts while also avoiding sample-to-sample variability, multi-step treatments, sample evolution effects, etc. This work presents the proof-of-concept of in-plane oxygen gradients, based on spatially resolved ex/in situ and novel fixed-energy X-ray absorption near edge spectroscopy (XANES), X-ray diffraction, ellipsometry and electrical resistivity measurements in hyper-stoichiometric La2NiO4+{\delta} and sub-stoichiometric (La,Sr)FeO3-{\delta} thin films. It thereby demonstrates the readiness and wide applicability of this innovative approach, which can be highly relevant for fundamental as well as applied research.
Materials Science (cond-mat.mtrl-sci)
Laser-induced topological phases in monolayer amorphous carbon
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Arnob Kumar Ghosh, Quentin Marsal, Annica M. Black-Schaffer
Driving non-topological materials out of equilibrium using time-periodic perturbations, such as circularly-polarized laser light, is a compelling way to engineer topological phases. At the same time, topology has traditionally only been considered for crystalline materials. Here we propose an experimentally feasible way of driving monolayer amorphous carbon topological. We show that circularly polarized laser light induces both regular and anomalous edge modes at quasienergies $ 0$ and $ \pm \pi$ , respectively. We also obtain complete topological characterization using an energy- and space-resolved topological marker based on the spectral localizer. Additionally, by introducing atomic coordination defects in the amorphous carbon, we establish the importance of the local atomic structure in topological amorphous materials. Our work establishes amorphous systems, including carbon, as a versatile and abundant playground to engineer topological phases.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Disordered Systems and Neural Networks (cond-mat.dis-nn)
4.5+2 pages, 4+2 figures; comments are welcome
Oxygen incorporation in YBa$_2$Cu$3$O${7-δ}$ thin films: surface activation and degradation
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-14 20:00 EDT
Alexander Stangl (1,2), Xavier Obradors (2), Anna Palau (2), Arnaud Badel (3), Teresa Puig (2) ((1) Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble, France, (2) Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Barcelona, Spain, (3) Univ. Grenoble Alpes, CNRS, Grenoble INP, G2ELab - Institut Néel, Grenoble, France)
The oxygen off-stoichiometry plays a pivotal role for the physical properties of superconducting oxides. Yet, there is a lack of knowledge on the fundamental processes of oxygen incorporation and correlated phenomena during oxygen post annealing treatments. Here, we deployed electrical probes ($ \rho(T)$ and electrical conductivity relaxation (ECR) measurements) to gain a better understanding of the kinetics of the oxygen reduction reaction (ORR) in epitaxial YBa$ _2$ Cu$ _3$ O$ _{7-\delta}$ (YBCO) thin films. We identified a new indicator for the onset temperature of oxygen incorporation and report for the first time drastic kinetic deactivation in bare YBCO. We demonstrate that surface decoration using silver micro islands both catalytically activates oxygen incorporation and bypasses surface degradation processes. Our results suggest that the ORR in the studied YBCO samples is limited by a surface reaction. Additionally, weak XRD signatures of the formation of extended bulk defects were identified, which have to be considered in the designing of an optimal oxygenation treatment to obtain best performing superconducting YBCO.
Superconductivity (cond-mat.supr-con)
Interpreting Aqueous Two-Phase Extraction of Single-Walled Carbon Nanotubes with Highly Versatile Nonionic Polymers
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Blazej Podlesny, Lukasz Czapura, Oussama Er-Riyahi, Karolina Z. Milowska, Dawid Janas
The development of efficient separation methods is essential for the production of fine chemicals and materials. Among them, the aqueous two-phase extraction (ATPE) allows for the isolation of single-walled carbon nanotubes (SWCNTs) of specific structures and other substances. However, this easy-to-use method, in which an analyte is partitioned between two phases, still demands a better understanding of its mechanism to make its application more effective. Herein, we demonstrate how various biphasic systems can be formed according to the nature of the phase-forming components. Moreover, by employing polyethylene-block-poly(ethylene glycol) (PEPEG), previously unrecognized in this context, we reveal the versatility of nonionic polymers for ATPE, which can successfully act as phase-forming compounds, partitioning modulators, and dispersing agents. Interestingly, as proven by experiments and modelling, PEPEG exhibited chirality-sensitive preference toward SWCNTs, which can significantly facilitate the purification of SWCNTs using various approaches. Capitalizing on this finding, we report how the extraction environment may be tailored to promote the isolation of (8,3) SWCNTs and other chirality-enriched SWCNT fractions. The relationships noted, based on the examination of a model material (SWCNTs), provide substantial insight into the elusive mechanism of the ATPE purification approach, widely employed across a range of analytes, from cell organelles to nanostructures
Materials Science (cond-mat.mtrl-sci)
Pages 1-23 (main text), pages 24-40 (supporting information)
Colorization of Optically Transparent Surfactants to Track Their Movement in Biphasic Systems Used for Differentiation of Nanomaterials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Blazej Podlesny, Lukasz Czapura, Dawid Janas
Aqueous two-phase extraction (ATPE) is a versatile method for the purification of numerous chemical compounds and materials, ranging from proteins and nucleic acids to cell organelles and various nanostructures. However, despite its widespread use, the underlying extraction mechanism remains unclear, which significantly reduces the utility of ATPE. Many types of surfactants are often added to biphasic systems to enhance the extraction of analytes between phases. Although their role in this process is crucial, it is not entirely understood. In this work, to fill this gap, we adapt and refine a nearly two-hundred-year-old chemical technique for the detection of bile salts in urine, referred to as Pettenkofer’s test and monitor the partitioning of single-walled carbon nanotubes (SWCNTs) by ATPE. This approach enabled us to tint the otherwise transparent bile salt surfactants to precisely track their distribution and concentration in the biphasic system, thereby unravelling the modus operandi of this popular purification technique.
Materials Science (cond-mat.mtrl-sci)
Pages 1-17 (main text), pages 18-33 (supporting information)
Anomalous Critical Behavior of Driven Disordered Systems Beyond the Overdamped Limit
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-08-14 20:00 EDT
Giuseppe Petrillo, Eduardo Jagla, Eugenio Lippiello, Alberto Rosso
We investigate the role of relaxation mechanisms in the driven response of elastic disordered interfaces in finite dimensions, focusing on the interplay between dimensionality and interaction range. Through extensive numerical simulations, we identify two distinct dynamical regimes. In two-dimensional systems with long-range interactions, we observe a regime of coexistence between pinned and flowing states. In contrast, for one-dimensional interfaces with long-range elasticity, as well as for short-range interactions in both 1D and 2D, the coexistence regime is absent. Nevertheless, the avalanche statistics differ significantly from those of overdamped systems: the usual power-law distribution is replaced by a pronounced bump, associated with large, anomalous avalanches that expand ballistically. We interpret these events as failed synchronization attempts and suggest they could be detected in experimental systems.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech)
Resonantly enhanced polariton-mediated superconductivity in a doped transition metal dichalcogenide monolayer
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Kenneth Choo, Olivier Bleu, Meera M. Parish, Jesper Levinsen
We present a proposal for achieving light-induced superconductivity using exciton polaritons - hybrid light-matter particles of excitons (bound electron-hole pairs) and microcavity photons. In contrast to previous theories of polariton-mediated superconductivity, which typically require multiple semiconductor layers, we show that superconductivity can be induced within a single semiconductor monolayer with inverted conduction bands, such as in the tungsten-based transition metal dichalcogenides. The key ingredient is that we can resonantly excite exciton polaritons into bands that are different from those occupied by the doped electrons, thus avoiding any Pauli blocking effects. Crucially, we can exploit the trion fine structure (i.e., multiple exciton-electron bound states) and tune the electron-polariton interactions via Feshbach resonances. Our theory of polariton-mediated superconductivity includes the energy dependence of the polariton-mediated interactions between electrons, as well as the polariton-induced changes to the electron quasiparticles. We find that superconductivity at elevated temperatures is within reach of current experiments.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas), Superconductivity (cond-mat.supr-con)
12 pages, 5 figures
Quasi-1D Electronic Metadevices with Enhanced Electrical Properties
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Abdallah Abushawish, Ziwen Huang, Mohammad Samizadeh Nikoo
Electronic metadevices leveraging sub-wavelength metallic features have shown great potential for high-frequency switching. Theoretical analysis based on a one-dimensional (1D) model indicates that reducing the size of subwavelength features can enhance electrical properties, such as contact resistance and switching cutoff frequency. Here, we report higher-than-expected contact resistance in electronic metadevices when the subwavelength feature size is aggressively downscaled. We attribute this effect to transverse currents in the two-dimensional electron gas (2DEG) running parallel to the stripe width. We present the first experimental demonstration of a metadevice governed by a one-dimensional model, which we refer to as a quasi-1D electronic metadevice and show that it enables enhanced electrical performance. Our findings pave the way to design next generation electronic metadevice switches with applications in future telecommunication circuits.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
Switching of a closed mobile vacancy based memristor, whose specific resistance linearly depends on local vacancy concentration
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-14 20:00 EDT
Irina V. Boylo, Konstantin L. Metlov
The linear (proportional to local vacancy concentration) term in specific resistance of the material does not directly contribute to the change of memristor’s total resistance when the vacancies are redistributed inside while keeping their total number constant. But it still changes kinetics of the vacancy drift under the influence of a passing electric current. These changes are especially significant in the presence of metal-insulator phase transition in the memristor’s material. In this paper, kinetic equation for local vacancy concentration is obtained, and exact solutions for its steady states are analyzed. It is shown that not only in the weakly nonlinear case (when the dependence of the specific resistance on the vacancy concentration can be neglected), but also in a strongly non-linear memristor with phase transition, its kinetics can be reduced to the classical exactly solvable Burgers equation.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 3 figures, bilingual: English (edited machine translation), Russian (primary)
Ratchet effect and jamming in dense mixtures of active and passive colloids in narrow pores
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
Frantisek Slanina, Miroslav Kotrla
Using the framework of generalized exclusion processes we study mixtures of passive and active particles interacting by steric repulsion. The particles move in a pore with periodically modulated aperture, which is modeled by a quasi-one-dimensional channel with periodic tooth-shaped profile. Internal driving of the active particles induces a ratchet current of these particles. In the current-density diagram, we observe three main regimes: of free flow; of thermally activated processes; of spinodal decomposition. When the density of particles is increased, we observe a transition to jammed state, where the ratchet current is substantially reduced. In time evolution, the transition to jammed state is seen as sudden drop of current at certain time. The probability distribution of these jamming times follows an exponential law. The average jamming time depends itself exponentially on the density of active particles. The coefficient in this exponential is nearly independent of the switching rate of the active particles as well as on the presence or absence of passive particles. Due to the interaction, the current of active particles imposes a drag on the passive particles. In the limit of both large systems and long times, the current of passive particles has always the same direction as the ratchet current of active particles. However, during the evolution of the system we observe very slow (logarithmic in time) approach to the asymptotic value, sometimes accompanied by current reversal, i.e. current of active and passive particles may go in opposite direction.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
13 pages, 16 figures
Phys. Rev. E 111 (2025) 015408
URhGe – Altermagnetic Ferromagnet
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-14 20:00 EDT
It is well known that the anomalous Hall effect in ferromagnetic and strongly paramagnetic metals in addition to electron skew scattering on impurities is determined by internal mechanism linked to the Berry curvature, a quantum-mechanical property of the electron states of a perfect crystal. Experimentally, however, it has been established that the Berry curvature does not play any role in the Hall resistance of the ferromagnet URhGe. URhGe is so called altermagnetic ferromagnet which crystal symmetry includes operation of time inversion only in combination with rotations and reflections. The explanation for strictly zero Berry curvature of electronic states in this material lies in the non-symmorphic symmetry of its crystal lattice.
Strongly Correlated Electrons (cond-mat.str-el)
3 pages, accepted for pubbl. in JETP Letters
Hydrodynamic approximations for driven dense colloidal mixtures in narrow pores
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
Frantisek Slanina, Miroslav Kotrla
The system of driven dense colloid mixtures is studied in one-, two- and three-dimensional geometries. We calculate the diffusion coefficients and mobilities for each particle type, including cross-terms, in a hydrodynamic limit, using a mean-field-type approximation. The set of non-linear diffusion equations are then solved. In one dimension, analytical results are possible. We show that in mixtures, the Brazil nut'' phenomenon, or depletion of larger particles by force of smaller ones, appears quite generically. We calculate the ratchet current and quantify the capability of sorting particles according to their size. We also indicate that the Brazil nut’’ effect lies behind the possibility of perfect separation, where large and big particles travel in strictly opposite direction.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
16 pages, 14 figures
Phys. Rev. E 107, (2023) 064606
Mid-infrared LEDs based on lattice-mismatched hybrid IV-VI/III-V heterojunctions
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Jarod E. Meyer, Biridiana Rodriguez, Leland Nordin, Kunal Mukherjee
Light-emitting diodes (LEDs) can bridge the gap between narrow linewidth, expensive lasers and broadband, inefficient thermal globars for low-cost chemical sensing in the mid-infrared (mid-IR). However, the efficiency of III-V based mid-IR LEDs at room temperature is low, primarily limited by strong nonradiative Auger-Meitner recombination that is only partially overcome with complex quantum-engineered active regions. Here, we exploit the intrinsically low Auger Meitner recombination rates of the IV-VI semiconductors PbSe and PbSnSe, while leveraging the mature III-V platform through the fabrication of hybrid heterojunctions that mediate the ~8% lattice mismatch to GaAs. Electrically injected n-PbSe/p-GaAs LEDs emit at 3.8 um with output powers up to 400 uW under pulsed operation and a peak wall plug efficiency of 0.08% at room temperature, approaching the performance of commercial III-V LEDs at similar wavelengths. Incorporating 7% Sn extends the emission to 5 um in GeSe/PbSnSe/GaAs LEDs with output powers up to 45 uW. Notably, both devices operate despite threading dislocation densities on the order of 1e9/cm^2, underscoring the potential of hybrid IV-VI/III-V heterojunction architectures. We show that combining the complementary advantages of IV-VI and III-V semiconductors offers a simple and efficient mid IR optoelectronic platform for a rapidly expanding set of applications.
Materials Science (cond-mat.mtrl-sci)
22 pages, 4 figures
Short-range and long-range correlations in driven dense colloidal mixtures in narrow pores
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
Frantisek Slanina, Miroslav Kotrla, Karel Netocny
The system of driven dense colloid mixture in a tube with diameter comparable with particle size is modeled by a generalization of asymmetric simple exclusion (ASEP) model. The generalization goes in two directions: relaxing the exclusion constraint by allowing several (but few) particles on a site, and by considering two species of particles, which differ by size and transport coefficients. We calculate the nearest-neighbor correlations using a variant of Kirkwood approximation and show by comparison with numerical simulations that the approximation provides quite accurate results. However, for long-range correlations, we show that the Kirkwood approximation is useless, as it predicts exponential decay of the density-density correlation function with distance, while simulation data indicate that the decay is algebraic. For one-component system, we show that the decay is governed by a power law with universal exponent close to 2. In two-component system, the correlation function behaves in more complicated manner; its sign oscillates but the envelope decays again very slowly and the decay is compatible with power-law with exponent somewhat lower than 2. Therefore, our generalization of ASEP belongs to different universality class than the ensemble of generalized ASEP models which are mappable to zero-range processes.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
14 pages, 13 figures
Phys. Rev. E 106, 014610 (2022)
Altermagnetic spintronics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
T. Jungwirth, J. Sinova, P. Wadley, D. Kriegner, H. Reichlova, F. Krizek, H. Ohno, L. Smejkal
The research landscape of magnetism has been recently enriched by the discovery of altermagnetism. It is an unconventional phase of matter characterized by a d-wave (or higher even-parity-wave) collinear compensated spin ordering, which enables strongly spin-polarized currents in the absence of magnetization, and features fast spin dynamics. Simultaneously, on the applied magnetism front, spintronic memories based on conventional ferromagnets are currently turning from a niche to a mass produced integrated-circuit technology as they start to complement semiconductors on advanced-node microprocessor chips. Our review connects these two rapidly developing science and technology fields by discussing how the unique signatures of altermagnetism can impact the functionality and scalability of future spintronic devices. As a reference, we first briefly recall the merits and physical limitations of the present ferromagnetic spintronic technology, and of proof-of-concept spintronic devices based on conventional collinear antiferromagnets and non-collinear compensated magnets. The main part of the review then focuses on physical concepts of the altermagnetic spintronics, and its potential interplay with ferroelectricity or superconductivity. We conclude with an outlook on the nascent experimental research of altermagnetic spintronics, and on the role of relativistic phenomena.
Materials Science (cond-mat.mtrl-sci)
15 pages, 4 figures
Discovery of a low-density filled-ice phase in nitrogen hydrate at high pressure
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Selene Berni, Sophie Espert, Tomasz Poreba, Simone Di Cataldo, Richard Gaal, Gabriel Tobie, Erwan Le Menn, Thomas C. Hansen, Roberto Bini, Livia Eleonora Bove
We map the high-pressure phase diagram of nitrogen hydrate up to 16 GPa at room temperature by combining neutron diffraction, Raman spectroscopy, and crystal structure prediction. We reveal a rich sequence of structural transformations, from sI/sII clathrates to hexagonal (sH) and tetragonal (sT) phases, culminating in a previously unknown orthorhombic filled-ice structure above 1.8 GPa in the Pnma space group, which we designate as NH-V. This new phase cannot be indexed to any known ice frameworks - such as the high-pressure methane hydrates MH-III (Imma) or MH-IV (Pmcn) - and exhibits a density approximately 30% lower than that of stable ice VII, pointing to distinctive water-nitrogen interactions. Our results refine the understanding of nitrogen hydrate behavior under extreme conditions and demonstrate the propensity of nitrogen and water to form stable filled-ice structures up to 16 GPa, with important implications for planetary science.
Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other)
Efficient predecision scheme for Metropolis Monte Carlo simulation of long-range interacting lattice systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
We propose a fast and general predecision scheme for Metropolis Monte Carlo simulation of $ d$ -dimensional long-range interacting lattice models. For potentials of the form $ V(r)=r^{-d-\sigma}$ , this reduces the computational complexity from $ O\left(N^2\right)$ to $ O\left(N^{2-\sigma/d}\right)$ for $ \sigma < d$ and to $ O\left(N \right)$ for $ \sigma > d$ , respectively. The algorithm is implemented and tested for several $ \mathrm{O}(n)$ spin models ranging from the Ising over the XY to the Edwards-Anderson spin-glass model. With the same random number sequence it produces exactly the same Markov chain as a simulation with explicit summation of all terms in the Hamiltonian. Due to its generality, its simplicity, and its reduced computational complexity it has the potential to find broad application and thus lead to a deeper understanding of the role of long-range interactions in the physics of lattice models, especially in nonequilibrium settings.
Statistical Mechanics (cond-mat.stat-mech), Computational Physics (physics.comp-ph)
Optical phonons as a testing ground for spin group symmetries
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
F. Schilberth, M. Kondákor, D. Ukolov, A. Pawbake, K. Vasin, O. Ercem, L. Prodan, V. Tsurkan, A. A. Tsirlin, C. Faugeras, P. Lemmens, K. Penc, I. Kézsmárki, S. Bordács, J. Deisenhofer
Lattice vibrations are highly sensitive to crystal symmetries and their changes across phase transitions. The latter can modify irreducible (co)representations and corresponding infrared and Raman selection rules of phonons. This concept is established for relativistic magnetic point groups, simultaneously transforming spatial and spin coordinates. However, in altermagnets described by non-relativistic spin groups with disjunct symmetry operations for both vector spaces, the phonon selection rules have remained unexplored. Here, we present a detailed study of the infrared- and Raman-active modes in the collinear antiferromagnet and altermagnet candidate Co$ _2$ Mo$ _3$ O$ _8$ . Comparing to ab initio calculations accurately capturing the eigenfrequencies, we identify all expected phonon modes at room temperature and deduce their selection rules using both symmetry approaches. Importantly, we observe the change of selection rules upon antiferromagnetic ordering, agreeing with the relativistic symmetry approach, while the spin group formalism predicts no changes. Therefore, optical phonons can reveal the appropriate symmetry treatment.
Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other)
Directed Cycles as Higher-Order Units of Information Processing in Complex Networks
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
Hardik Rajpal, Paul Expert, Vaiva Vasiliauskaite
Directed cycles form the fundamental motifs in natural, social and artificial networks, yet their distinct computational roles remain under-explored, particularly in the context of higher-order structure and function. In this work, we investigate how two types of directed cycles - feedforward and feedback - can act as higher-order structures to facilitate the flow and integration of information in sparse random networks, and how these roles depend on the environment of the cycles. Using information-theoretic measures, we show that network size, sparsity and relative directionality critically impact the information-processing capacities of directed cycles. In a network with no-preferred global direction, a feedforward cycle enables greater information flow and a feedback cycle allows for increased information integration. The relative direction of a feedforward cycle as well as the structural incoherence it induces, determines its capacity to generate higher-order behaviour. Finally, we demonstrate that introducing feedback loops into otherwise feedforward architectures increases the diversity of network activity patterns. These findings suggest that directed cycles serve as computational motifs with local information processing capabilities that depend on the structure they are embedded. Using directed cycles, we highlight the interdependence between higher-order structures and the higher-order order behaviour they can induce in the network dynamics.
Statistical Mechanics (cond-mat.stat-mech), Information Theory (cs.IT), Dynamical Systems (math.DS)
Self-propulsion via non-transitive phase coexistence in chemically active mixtures
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
Yicheng Qiang, Chengjie Luo, David Zwicker
Phase separation drives the formation of biomolecular condensates in cells, which comprise many components and sometimes possess multiple phases. The equilibrium physics of phase separation is well understood, but many components in condensates undergo active reactions. We demonstrate that such reactions affect phase separation by altering the chemical potential balance and by introducing an osmotic pressure difference at interfaces. However, the system does not permit a pseudo-pressure balance, and bulk compositions depend on which phases are in contact. Moreover, phase coexistence is no longer transitive, which enables self-propelled phases and more complex dynamics.
Soft Condensed Matter (cond-mat.soft)
5 pages, 4 figures, with appendix
Dynamics of phase separation in non-local elastic networks
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
Oliver W. Paulin, Yicheng Qiang, David Zwicker
Phase separation of a liquid mixture embedded within an elastic network is relevant to a wide range of natural and industrial systems, including biomolecular condensates interacting with the cytoskeleton, structural colouring in bird feathers, and gas bubbles forming within soft sediments. Recent experiments in synthetic polymer gels have demonstrated that when the size of phase-separated domains is comparable to the characteristic pore size of the network, a patterned phase with a well-defined length scale may emerge. Theoretical works based on an equilibrium approach have attributed this pattern formation to non-local elastic effects arising from heterogeneity of the underlying network. Here, we extend these ideas by developing a dynamic theory in which phase separation is coupled to non-local elasticity via the framework of large-deformation poroelasticity. We study our model via both linear stability analysis and numerical simulation, identifying the parameter space in which phase separation occurs, and investigating the impact of different elasticity models. We find that although local elasticity can inhibit phase separation and affect domain count, it is unable to completely suppress coarsening. In contrast, non-local elasticity arrests coarsening to form patterned domains with a well-defined length scale that decreases with increasing stiffness. Our modelling framework thus paves the way for quantitative comparisons between simulations and experiments, for example by considering a strain-stiffening network rheology.
Soft Condensed Matter (cond-mat.soft)
Learning complexity of many-body quantum sign structures through the lens of Boolean Fourier analysis
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-08-14 20:00 EDT
Ilya Schurov, Anna Kravchenko, Mikhail I. Katsnelson, Andrey A. Bagrov, Tom Westerhout
We study sign structures of the ground states of spin-$ 1/2$ magnetic systems using the methods of Boolean Fourier analysis. Previously it was shown that the sign structures of frustrated systems are of complex nature: specifically, neural networks of popular architectures lack the generalization ability necessary to effectively reconstruct sign structures in supervised learning settings. This is believed to be an obstacle for applications of neural quantum states to frustrated systems. In the present work, we develop an alternative language for the analysis of sign structures based on representing them as polynomial functions defined on the Boolean hypercube - an approach called Boolean Fourier analysis. We discuss the relations between the properties of the Boolean Fourier series and the learning complexity of sign structures, and demonstrate that such polynomials can potentially serve as variational ansätze for the complex sign structures that dramatically outperform neural networks in terms of generalization ability. While ansätze of this type cannot yet be directly used in the context of variational optimization, they indicate that the complexity of sign structures is not an insurmountable curse, and can potentially be learned with better designed NQS architectures. Finally, we show how augmenting data with Boolean functions can aid sign prediction by neural networks.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Strongly Correlated Electrons (cond-mat.str-el), Discrete Mathematics (cs.DM), Quantum Physics (quant-ph)
29 pages, 14 figures, 1 table; the figures will be updated to publication quality
Emergent Hydrodynamics in an Exclusion Process with Long-Range Interactions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
Ali Zahra, Jerome Dubail, Gunter M. Schütz
We study the symmetric Dyson exclusion process (SDEP) - a lattice gas with exclusion and long-range, Coulomb-type interactions that emerge both as the maximal-activity limit of the symmetric exclusion process and as a discrete version of Dyson’s Brownian motion on the unitary group. Exploiting an exact ground-state (Doob) transform, we map the stochastic generator of the SDEP onto the spin-$ 1/2$ XX quantum chain, which in turn admits a free-fermion representation. At macroscopic scales we conjecture that the SDEP displays ballistic (Eulerian) scaling and non-local hydrodynamics governed by the equation $ \partial_t \rho+\partial_x j[\rho]=0$ with $ j[\rho]=(1/\pi)\sin(\pi\rho(x,t))\sinh(\pi\mathcal{H}\rho(x,t))$ , where $ \mathcal{H}$ is the Hilbert transform, making the current a genuinely non-local functional of the density. This non-local one-field description is equivalent to a local two-field “complex Hopf” system for finite particle density. Closed evolution formulas allow us to solve the melting of single and double block initial states, producing limit shapes and arctic curves that agree with large-scale Monte Carlo simulations. The model thus offers a tractable example of emergent non-local hydrodynamics driven by long-range interactions.
Statistical Mechanics (cond-mat.stat-mech), Mathematical Physics (math-ph)
Doping Evolution of Nodal Electron Dynamics in Trilayer Cuprate Superconductor Bi$_2$Sr$_2$Ca$_2$Cu$3$O${10+δ}$ Revealed by Laser-Based Angle-Resolved Photoemission Spectroscopy
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-14 20:00 EDT
Hao Chen, Jumin Shi, Xiangyu Luo, Yinghao Li, Yiwen Chen, Chaohui Yin, Yingjie Shu, Jiuxiang Zhang, Taimin Miao, Bo Liang, Wenpei Zhu, Neng Cai, Xiaolin Ren, Chengtian Lin, Shenjin Zhang, Zhimin Wang, Fengfeng Zhang, Feng Yang, Qinjun Peng, Zuyan Xu, Guodong Liu, Hanqing Mao, Xintong Li, Lin Zhao, X. J. Zhou
The doping evolution of the nodal electron dynamics in the trilayer cuprate superconductor Bi$ _2$ Sr$ _2$ Ca$ _2$ Cu$ _3$ O$ _{10+\delta}$ (Bi2223) is investigated using high-resolution laser-based angle-resolved photoemission spectroscopy (ARPES). Bi2223 single crystals with different doping levels are prepared by controlled annealing which cover the underdoped, optimally-doped and overdoped regions. The electronic phase diagram of Bi2223 is established which describes the T$ _\mathrm{c}$ dependence on the sample doping level. The doping dependence of the nodal Fermi momentum for the outer (OP) and inner (IP) CuO$ _2$ planes is determined. Charge distribution imbalance between the OP and IP CuO$ _2$ planes is quantified, showing enhanced disparity with increasing doping. Nodal band dispersions demonstrate a prominent kink at $ \sim$ 94$ ,$ meV in the IP band, attributed to the unique Cu coordination in the IP plane, while a weaker $ \sim$ 60$ ,$ meV kink is observed in the OP band. The nodal Fermi velocity of both OP and IP bands is nearly constant at $ \sim$ 1.62$ ,$ eVÅ independent of doping. These results provide important information to understand the origin of high T$ _\mathrm{c}$ and superconductivity mechanism in high temperature cuprate superconductors.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
18 pages, 4 figures
Chinese Physics B 34, 077404 (2025)
Spin-chirality-dependent modulation of topological gap, Chern number, and valley-polarization in monolayer Kagome materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
Wenzhe Zhou, Guibo Zheng, Yating Li, Zhenzhen Wan, Aolin Li, Fangping Ouyang
Kagome materials exhibit unique electronic properties, such as the quantum anomalous Hall effect. The control of Chern numbers is critical for quantum device manipulation, but existing research has mainly focused on collinear magnetization while neglecting chiral spin textures. Through first-principles calculations and tight-binding modeling of monolayer Cr3Se4, this study reveals spin chirality-dependent control of topological gaps, Chern numbers, and valley polarization in kagome materials. The results demonstrate that the azimuthal angle has no observable effect. For collinear magnetization, the topological bandgap decreases as the spin orientation approaches the in-plane direction. In the breathing Kagome lattice, the degeneracy between K and K’ valleys is lifted, and increasing the polar angle induces successive closing and reopening of the valleys. For chiral spin textures, increasing polar angle enlarges the bandgap when chirality \k{appa} = 1, while reducing it when \k{appa} = -1. Moreover, spin chirality enables the quantum anomalous Hall state without spin-orbit coupling. Structural asymmetry and spin chirality effectively modulate the bandgap, Chern number, and valley polarization. These findings provide strategies for controlling topological states and advancing applications in quantum devices and valleytronic systems.
Materials Science (cond-mat.mtrl-sci)
16 pages, 6 figures. Submitted to Physical Review B
Binary Mixtures in Linear Convection Arrays
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-14 20:00 EDT
Pulak Kumar Ghosh, Yuxin Zhou, Yunyun Li, Fabio Marchesoni, Franco Nori
We numerically investigated the dynamics of a mixture of finite-size active and passive particles in a linear array of convection rolls. The interplay of advection and steric interactions produces a number of interesting effects, like the stirring of a passive colloidal fluid by a small fraction of slow active particles, or the separation of the mixture active and passive colloidal fractions by increasing the motility of the active one, which eventually clusters in stagnation areas along the array walls. These mechanisms are quantitatively characterized by studying the dependence of the diffusion constants of the active and passive particles on the parameters of the active mixture fraction.
Soft Condensed Matter (cond-mat.soft)
7 figures
ChemPhysChem, 24, e202200471 (2023)
Strain-driven feedback tunes memory and relaxation in a Mott insulator far from equilibrium
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-14 20:00 EDT
O. Yu. Gorobtsov, Y. Kalcheim, Z. Shao, A. Shabalin, N. Hua, D. Weinstock, R. Bouck, M. Seaberg, D. Zhu, O. G. Shpyrko, I. K. Schuller, A. Singer
Memory effects in metal-insulator transitions in quantum materials reveal complex physics and potential for novel technologies mimicking biological neural systems. Nonetheless, understanding of memory and nonlinearity in non-equilibrium transitions remains elusive as they can involve timescales from femtoseconds to microseconds. In this study, we extend time-resolved x-ray Bragg diffraction to the necessary high dynamic range of timescales to fully trace the pathways of far-from-equilibrium photoexcited transitions in epitaxial films of V2O3, a technologically promising prototypical Mott insulator. We find a 105 times adjustment in relaxation time: the memory of spatial and energy heterogeneity during transition causes a Kohlrausch-Williams-Watts shaped relaxation lingering over a hundred microseconds versus nanoseconds. The dramatic slowdown in the light-driven highly correlated system accompanies heterogeneous excitation barriers, as in neural systems.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
Active Particle Diffusion in Convection Roll Arrays
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-14 20:00 EDT
Pulak Kumar Ghosh, Fabio Marchesoni, Yunyun Li, Franco Nori
We numerically investigated the Brownian motion of active Janus particles in a linear array of planar counter-rotating convection rolls at high Péclet numbers. Similarly to passive particles, active microswimmers exhibit advection enhanced diffusion, but only for self-propulsion speeds up to a critical value. The diffusion of faster Janus particles is governed by advection along the array’s edges, whereby distinct diffusion regimes are observed and characterized. Contrary to passive particles, the relevant spatial distributions of active Janus particles are inhomogeneous. These peculiar properties of active matter are related to the combined action of noise and self-propulsion in a confined geometry and hold regardless of the actual flow boundary conditions.
Statistical Mechanics (cond-mat.stat-mech)
Phys. Chem. Chem. Phys. 23, 11944(2021)
2D bilayer electron-hole superfluidity with unequal and anisotropic masses
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-14 20:00 EDT
We investigate the stability of electron-hole superfluidity in two-dimensional bilayers with unequal and anisotropic effective masses. Using a zero-temperature, self-consistent Hartree-Fock approach, we study two experimentally relevant deviations from the ideal equal-mass isotropic case: (i) isotropic but unequal conduction and valence band masses ($ m_c^\ast \neq m_v^\ast$ ), and (ii) equal average masses with orthogonal in-plane anisotropies $ (m_{c,x}^\ast, m^\ast_{c,y}) = (m_1^\ast, m_2^\ast)$ and $ (m^\ast_{v,x}, m^\ast_{v,y}) = (m_2^\ast, m_1^\ast)$ . For both scenarios, we compute the order parameter and analyze the BEC-BCS crossover as a function of layer separation and mass ratio. We find that both mass imbalance and mass anisotropy reduce the pairing strength and suppress the inferred critical temperature $ T_c$ by breaking perfect Fermi surface nesting, and shift the BEC-BCS crossover. Despite these effects, superfluidity remains robust across the full range of densities and interlayer separations considered, with no transition to an unpaired plasma state in the absence of screening. Our results provide a baseline for understanding the interplay of mass mismatch and anisotropy in current and emerging bilayer platforms, including van der Waals heterostructures and anisotropic two-dimensional semiconductors. Our work also establishes that Fermi surface nesting is not a key ingredient for the bilayer superfluidity, which is always the ground state for all electron-hole bilayers although the resultant $ T_c$ depends on the parameter details and may very well be unmeasurably low for large interlayer separations.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)