CMP Journal 2025-05-19
Statistics
Nature: 1
Nature Nanotechnology: 3
Nature Reviews Physics: 2
arXiv: 54
Nature
Genomics reveals zoonotic and sustained human Mpox spread in West Africa
Original Paper | Molecular evolution | 2025-05-18 20:00 EDT
Edyth Parker, Ifeanyi F. Omah, Delia Doreen Djuicy, Andrew Magee, Christopher H. Tomkins-Tinch, James Richard Otieno, Patrick Varilly, Akeemat Opeyemi Ayinla, Ayotunde E. Sijuwola, Muhammad I. Ahmed, Oludayo O. Ope-ewe, Olusola Akinola Ogunsanya, Alhaji Olono, Femi Mudasiru Saibu, Philomena Eromon, Moïse Henri Moumbeket Yifomnjou, Loique Landry Messanga Essengue, Martial Gides Wansi Yonga, Gael Dieudonné Essima, Ibrahim Pascal Touoyem, Landry Jules Mouliem Mounchili, Sara Irene Eyangoh, Alain Georges Mballa Etoundi, Linda Esso, Inès Mandah Emah Nguidjol, Steve Franck Metomb, Cornelius Chebo, Samuel Mbah Agwe, Hans Makembe Mossi, Chanceline Ndongo Bilounga, Olusola Akanbi, Abiodun Egwuenu, Odianosen Ehiakhamen, Chimaobi Chukwu, Kabiru Suleiman, Afolabi Akinpelu, Adama Ahmad, Khadijah Isa Imam, Richard Ojedele, Victor Oripenaye, Kenneth Ikeata, Sophiyah Adelakun, Babatunde Olajumoke, Áine O’Toole, Mark Zeller, Karthik Gangavarapu, Daniel J. Park, Gerald Mboowa, Sofonias Kifle Tessema, Yenew Kebede Tebeje, Onikepe Folarin, Anise Happi, Philippe Lemey, Marc A. Suchard, Kristian G. Andersen, Pardis Sabeti, Andrew Rambaut, Chikwe Ihekweazu, Idris Jide, Ifedayo Adetifa, Richard Njouom, Christian T. Happi
Five years before the 2022 multi-country mpox outbreak, Nigeria and Cameroon reported their first cases in over three decades.1,2 While Nigeria’s outbreak is recognized as an ongoing human epidemic, the drivers of Cameroon’s resurgence remain unclear.3,4 The rate of zoonoses remains uncertain in both countries, and gaps in genomic data obscure the timing, zoonotic and geographic origin of mpox virus (MPXV) emergence in humans. To address these uncertainties, we generated 118 MPXV genomes from Nigeria and Cameroon from 2018-2023. Our findings show that, in contrast to Nigeria, cases in Cameroon are the result of repeated zoonoses, with two distinct zoonotic lineages circulating across the Nigeria-Cameroon border. Our findings suggest that shared animal populations in the cross-border forest ecosystems drive virus emergence and spread. Accordingly, we identify the closest zoonotic outgroup to the Nigerian human epidemic lineage (hMPXV-1) in a southern Nigerian border state. We estimate that the shared ancestor of the zoonotic outgroup and hMPXV-1 circulated in animals in southern Nigeria in late 2013. We estimate that hMPXV-1 emerged in humans in August 2014 in the southern Rivers State and circulated undetected for three years. Rivers State acted as the main source of viral spread across the human epidemic. Our study sheds light on MPXV’s recent establishment in the human population and highlights the risk of persistent zoonotic emergence of MPXV in the complex border regions of Cameroon and Nigeria.
Molecular evolution, Viral infection
Nature Nanotechnology
Tumour-derived microparticles obtained through microwave irradiation induce immunogenic cell death in lung adenocarcinoma
Original Paper | Drug delivery | 2025-05-18 20:00 EDT
Yali Wu, Wenjuan Chen, Jingjing Deng, Xinghui Cao, Zimo Yang, Jiangbin Chen, Qi Tan, E. Zhou, Minglei Li, Jiatong Liu, Mengfei Guo, Yang Jin
Tumour-derived microparticles (TMPs), extracellular vesicles traditionally obtained upon ultraviolet (UV) radiation of tumour cells, hold promise in tumour immunotherapies and vaccines and have demonstrated potential as drug delivery systems for tumour treatment. However, concerns remain regarding the limited efficacy and safety of UV-derived TMPs. Here we introduce a microwave (MW)-assisted method for preparing TMPs, termed MW-TMPs. Brief exposure of tumour cells to short-wavelength MW radiation promotes the release of TMPs showing superior in vivo antitumour activity and safety compared with UV-TMPs. MW-TMPs induce immunogenic cell death and reprogramme suppressive tumour immune microenvironments in different lung tumour models, enabling dual targeting of tumour cells by natural killer and T cells. We show that they can efficiently deliver methotrexate to tumours, synergistically boosting the efficacy of PD-L1 blockade. This MW-TMP development strategy is simpler, more efficient and safer than traditional UV-TMP methods.
Drug delivery, Nanoparticles
Electric bias-induced reversible configuration of single and heteronuclear dual-atom catalysts on 1Tʹ-MoS2
Original Paper | Electrocatalysis | 2025-05-18 20:00 EDT
Jianhua Wu, Zhongxin Chen, Ke Yang, Xin Zhou, Huizhi Li, Zhiyong Wang, Mengyao Su, Rongrong Zhang, Tie Wang, Qikun Hu, Ning Yan, Cuibo Liu, Bin Zhang, Ming Yang, Shibo Xi, Kian Ping Loh
The development of substrates capable of anchoring single-atom catalysts (SACs) while enabling their dynamic reconfiguration into heteronuclear dual-atom catalysts (DACs) holds considerable promise for electrochemical synthesis, yet remains underexplored. Here we show that electrochemical desulfurization of MoS2 generates vacancy-rich 1T’ domains, which support high loadings of Cu (7.9 wt%) and Pt (6.7 wt%) SACs that are well-positioned for dynamic sintering to form DACs. Operando X-ray absorption spectroscopy and density functional theory calculations reveal a voltage-driven, reversible transformation between individual Pt/Cu SACs and Cu-Pt DAC configurations during hydrogen evolution reaction potentials. The electric-field-induced Cu-Pt DACs exhibit superior performance in the selective hydrogenation of alkynes compared with their monometallic SAC counterparts. This work underscores vacancy-enriched 1T’-MoS2 as a versatile platform for high-density SAC deposition, enabling on-demand structural reconfiguration and paving the way for tailored catalyst design in electrosynthesis.
Electrocatalysis, Two-dimensional materials
A collagenase nanogel backpack improves CAR-T cell therapy outcomes in pancreatic cancer
Original Paper | Drug delivery | 2025-05-18 20:00 EDT
Zhipeng Zhao, Qian Li, Chenghao Qu, Zeyu Jiang, Guoqing Jia, Gongde Lan, Yuxia Luan
Chimeric antigen receptor (CAR) T cell therapy has revolutionized the treatment of haematological malignancies. Challenges in overcoming physical barriers however greatly limit CAR-T cell efficacy in solid tumours. Here we show that an approach based on collagenase nanogel generally improves the outcome of T cell-based therapies, and specifically of CAR-T cell therapy. The nanogels are created by cross-linking collagenase and subsequently modifying them with a CXCR4 antagonist peptide. These nanogels can bind CAR-T cells via receptor-ligand interaction, resulting in cellular backpack delivery systems. The nanogel backpacks modulate tumoural infiltration and localization of CAR-T cells by surmounting physical barriers and disrupting chemokine-mediated CAR-T cell imprisonment, thereby addressing their navigation deficiency within solid tumours. Our approach offers a promising strategy for pancreatic cancer therapy and holds potential for advancing CAR-T cell therapy towards clinical applications.
Drug delivery, Nanoparticles
Nature Reviews Physics
Challenges and opportunities in exascale fusion simulations
Review Paper | Computer science | 2025-05-18 20:00 EDT
Marta Garcia-Gasulla, Mervi J. Mantsinen
The challenging computational requirements of nuclear fusion research arise from the multiple timescales and space scales involved in the physics and engineering processes of a fusion device. Owing to the intrinsic and complex interconnections of these processes, the complex multiphysics and multiscale nature of fusion simulations require the capabilities of cutting-edge supercomputers. Advances in supercomputing enable a move towards larger-scale, higher-fidelity full fusion reactor digital models that capture not only the plasma core and edge physics but also interactions with materials and engineering aspects, such as fusion reactor walls and cooling systems. This Perspective discusses the main opportunities that fusion codes face in the transition to the emerging exascale systems and beyond, and the challenges that remain to be overcome.
Computer science, Engineering, Materials for energy and catalysis, Nuclear fusion and fission, Plasma physics
Yielding and plasticity in amorphous solids
Review Paper | Colloids | 2025-05-18 20:00 EDT
Ludovic Berthier, Giulio Biroli, Lisa Manning, Francesco Zamponi
Disordered media include metallic glasses, colloidal suspensions, granular matter and biological tissues, among others. Their physics offers difficult challenges because it often occurs far from equilibrium, in materials that lack symmetries and that evolve through complex energy landscapes. We review theoretical efforts from recent years to provide microscopic insights into the mechanical properties of amorphous media using approaches from statistical mechanics as unifying frameworks. Our focus is on how amorphous solids become unstable and yield under applied deformations. We cover both the initial regime, corresponding to small deformations of the solid, and the transition between elastic response and plastic flow when the solid yields. We discuss the specific features arising for systems evolving near a jamming transition and extend our discussion to recent studies of the rheology of dense biological and active materials. We emphasize the importance of a unified approach to studying the response to deformation and the yielding instability of a broad range of disordered media.
Colloids, Statistical physics
arXiv
Nonreciprocal spin waves in out-of-plane magnetized waveguides reconfigured by domain wall displacements
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
H. Mortada, R. Verba, Q. Wang, P. Pirro, A. Hamadeh
Wave-based platforms for novel unconventional computing approaches like neuromorphic computing require a well-defined, but adjustable flow of wave information combined with non-volatile data storage elements to implement weights which allow for training and learning. Due to their inherent nonreciprocal properties and their direct physical interaction with magnetic data storage, spin waves are ideal candidates to realize such platforms. In the present study, we show how spin-wave nonreciprocity induced by dipolar interactions of nanowaveguides with antiparallel, out-of-plane magnetization orientations can be used to create a spin-wave circulator allowing for unidirectional information transport and complex signal routing. In addition, the device can be reconfigured by a magnetic domain wall with adjustable position, which allows for a non-volatile tuning of the nonreciprocity and signal propagation. These properties are demonstrated for a spin-wave directional coupler through a combination of micromagnetic simulations and analytical modeling also showing that it functions as a waveguide crossing element, tunable power splitter, isolator, and frequency multiplexer. As magnetic material, out-of-plane magnetized Bismuth-doped Yttrium Iron Garnet has been considered. For this material, the motion of domain walls by magnonic spin transfer torque has been recently experimentally demonstrated which enables to store results from spin-wave computation. In combination with the presented concept of domain wall based reconfiguration and nonlinear spin-wave dynamics, this enables for the creation of a nano-scaled nonlinear wave computing platform with the capability for self-learning.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
Spatially patterned phases in a reaction-time-symmetry-broken model of flocking
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-05-19 20:00 EDT
Charles R. Packard, Daniel M. Sussman
We introduce a Vicsek-like flocking model with a minimal form of time-delayed orientational interactions, in which the delays occur on a time scale that is well-separated from other time scales in the model. We achieve this by implementing an ``index-ordered’’ update rule, mimicking a scenario in which agents have a distribution of times with which they react to information. This model retains the usual disorder-to-order transition common in flocking models, but we show that it also possesses a second transition, deep in the polar flocking phase, to a state with spatially patterned transverse velocities. We characterize this transition and its sensitivity to finite-size effects using the Binder cumulant, and demonstrate – via direct measurements and by measuring a susceptibility of the phase to particle index permutations – that the stability of this phase is directly tied to a subtle spatial organization of a slow-relaxing index-order field. These results highlight the potential for even seemingly insignificant temporal asymmetries to fundamentally alter the collective behavior of active matter.
Soft Condensed Matter (cond-mat.soft)
7 pages, 6 figures, and a lot of underlying simulation data
Achieving accurate entropy and melting point by ab initio molecular dynamics and zentropy theory: Application to fluoride and chloride molten salts
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Shun-Li Shang, Nigel L. E. Hew, Rushi Gong, Cillian Cockrell, Paul A. Bingham, Xiaofeng Guo, Qijun Hong, Zi-Kui Liu
We have recently developed a breakthrough methodology for rapidly computing entropy in both solids and liquids by integrating a multiscale entropy approach (known as zentropy theory) with molecular dynamics (MD) simulations. This approach enables entropy estimation from a single MD trajectory by analyzing the probabilities of local structural configurations and atomic distributions, effectively addressing the long-standing challenge of capturing configurational entropy. Here, we demonstrate the power of this method by predicting entropies, enthalpies, and melting points for 25 binary and ternary chlorite- and fluoride-based molten salts using ab initio MD (AIMD) simulations. The strong agreement between our predictions and experimental data underscores the potential of this approach to transform computational thermodynamics, offering accurate, efficient, and direct predictions of thermodynamic properties across both solid and liquid phases.
Materials Science (cond-mat.mtrl-sci)
30 pages, 7 figures, 1 table in main text, together with 4 supplementary figures and 1 supplementary table
An infinite grid of mesoscopic resistors: investigation and visualization of ballistic conduction
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
A square lattice of mesoscopic resistors is considered. Each bond is modeled as a narrow waveguide, while junctions are sources of elastic scattering given by a scattering matrix \mathbf{S}. Symmetry and unitarity constraints are used in a detailed way to simplify all possible matrices \mathbf{S}. Energetic band structure of the system is determined and visualized for exemplary parameters. Conductance between external electrodes attached to two arbitrary nodes is given by the Landauer formula. Thus the transmittance between the electrodes is calculated. The rest of the paper is devoted to studying wave function patterns arising from an electron injected through one electrode into the system. It is observed that depending on its energy both dull and localized or intricate and expansive patterns occur. It is justified mathematically that fitting electron energy into an energy band can be associated with emergence of complex patterns. Finally, possible experimental realizations of the considered model are briefly mentioned.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Microscopic description of the liquid-gas coexistence curve for Morse fluids in the immediate vicinity of the critical point
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-05-19 20:00 EDT
I.V. Pylyuk, M.P. Kozlovskii, R.V. Romanik
The present work is aimed at investigating the behavior of Morse fluids in the immediate vicinity of the critical point within the framework of a cell model. This region is of both fundamental and practical importance, yet presents analytical challenges due to the significant influence of order parameter fluctuations. An analytical procedure is developed to construct the upper part of the liquid-gas coexistence curve and calculate its diameter, incorporating the non-Gaussian (quartic) distribution of fluctuations. An explicit expression is derived for the temperature-dependent analytical term appearing in the expression for the rectilinear diameter. The numerical evaluation of the relevant quantities is carried out using Morse potential parameters representative of sodium. The coexistence curve is constructed both with and without the inclusion of the analytical temperature-dependent term in the calculation. A specific condition is identified under which the agreement between the presented binodal branches and Monte Carlo simulation data from other study, extrapolated to the immediate vicinity of the critical point, is improved. It is shown that better agreement is achieved when the analytical term is included in the calculation of the liquid branch and omitted in the gas branch. The proposed analytical approach may provide useful insight for the theoretical study of critical phenomena in more complex fluid systems.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
17 pages, 4 figures
New generation of cavity microscope for quantum simulations
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-05-19 20:00 EDT
Gaia Stella Bolognini, Zeyang Xue, Michael Alexander Eichenberger, Nick Sauerwein, Francesca Orsi, Ekaterina Fedotova, Rohit Prasad Bhatt, Jean-Philippe Brantut
We present the design and assembly of a cavity microscope for quantum simulations with ultracold atoms. The system integrates a high-finesse optical cavity with a pair of high-numerical aperture lenses sharing a common optical axis, enabling simultaneous operation with light close-to-atomic resonance. The system keeps the advantages of a rigid, single-block structure holding the lenses and cavity together, and improves over existing designs by using most of the solid angle left free by the cavity mode for imaging and atomic manipulation purposes. The cavity has a length of $ 19.786$ mm, a finesse of $ 2.35\times 10^4$ and operates $ 214\mu\text{m}$ away from the concentric limit, deep in the strong coupling regime. The two lenses offer a numerical aperture of $ 0.52$ each and maximal optical access in all directions transverse to the cavity axis, compatible with applications in quantum-gas microscopes, micro-tweezer arrays or few-fermions systems, as well as future cavity-assisted quantum simulation protocols demanding sub-cavity-mode control of the atom-cavity coupling.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph), Instrumentation and Detectors (physics.ins-det), Optics (physics.optics), Quantum Physics (quant-ph)
9 pages, 4 figures
Exact multiple anomalous mobility edges in a flat band geometry
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-05-19 20:00 EDT
Zhanpeng Lu, Hui Liu, Yunbo Zhang, Zhihao Xu
Anomalous mobility edges(AMEs), separating localized from {multifractal critical states}, represent a novel form of localization transition in quasiperiodic systems. However, quasi-periodic models exhibiting exact {AMEs} remain relatively rare, limiting the understanding of these transitions. In this work, we leverage the geometric structure of flat band models to construct exact {AMEs}. Specifically, we introduce an anti-symmetric diagonal quasi-periodic mosaic modulation, which consists of both quasi-periodic and constant potentials, into a cross-stitch flat band lattice. When the constant potential is zero, the system resides entirely in a localized phase, with its dispersion relation precisely determined. For non-zero constant potentials, we use a simple method to derive analytical solutions for a class of {AMEs}, providing exact results for both the {AMEs} and the system’s localization and critical properties. Additionally, we propose a classical electrical circuit design to experimentally realize the system. This study offers valuable insights into the existence and characteristics of {AMEs} in quasi-periodic systems.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Quantum Physics (quant-ph)
10 pages, 9 figures; Version accepted by FOP
Crescent domain-wall pairs in anisotropic two-dimensional MnOI monolayer with fast dynamics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Yijun Yang, Zhong Shen, Jun Chen, Shuai Dong, Xiaoyan Yao
The controllable and efficient manipulation is always a key challenge for the application of topological magnetic textures in spintronic devices. By first-principles calculations and atomistic simulations, the present work reveals an exotic domain-wall pair in crescent shape, which possesses topology in one dimension and particle-like robustness in two dimensions. Its antiferromagnetic version is observed in the two-dimensional MnOI monolayer with a strong anisotropy, and the ferromagnetic version exists under an appropriate strain. Both of them can be driven efficiently by current to move in a straight line along a certain direction. Hereby, another possible path is provided to realize the application of topological magnetic texture in the next-generation high-speed spintronic devices.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Phys. Rev. B 111, 184417 (2025)
Sequential topology: iterative topological phase transitions in finite chiral structures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
Maxine M. McCarthy, D. M. Whittaker
We present theoretical and experimental results probing the rich topological structure of arbitrarily disordered finite tight binding Hamiltonians with chiral symmetry. We extend the known classification by considering the topological properties of phase boundaries themselves. That is, can Hamiltonians that are confined to being topologically marginal, also have distinct topological phases? For chiral structures, we answer this in the affirmative, where we define topological phase boundaries as having an unavoidable increase in the degeneracy of real space zero modes. By iterating this question, and considering how to enforce a Hamiltonian to a phase boundary, we give a protocol to find the largest dimension subspace of a disordered parameter space that has a certain order degeneracy of zero energy states, which we call \textit{sequential topology}. We show such degeneracy alters localisation and transport properties of zero modes, allowing us to experimentally corroborate our theory using a state-of-the-art coaxial cable platform. Our theory applies to systems with an arbitrary underlying connectivity or disorder, and so can be calculated for any finite chiral structure. Technological and theoretical applications of our work are discussed.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Disordered Systems and Neural Networks (cond-mat.dis-nn)
16 pages, 10 figures
Topological surface states in γ-PtBi$_2$ evidenced by scanning tunneling microscopy
New Submission | Superconductivity (cond-mat.supr-con) | 2025-05-19 20:00 EDT
Yunkai Guo, Jingming Yan, Wen-Han Dong, Yongkai Li, Yucong Peng, Xuetao Di, Caizhen Li, Zhiwei Wang, Yong Xu, Peizhe Tang, Yugui Yao, Wenhui Duan, Qi-Kun Xue, Wei Li
For the application of topological materials, the specific location of their topological surface states with respect to the Fermi level are important. {\gamma}-PtBi2 has been demonstrated to be a Weyl semimetal possessing superconducting Fermi arcs by photoemission spectroscopy. However, the evidence of its topological surface states is lacking by scanning tunneling microscopy (STM), which should be rather sensitive to detect the surface states. Here, we show multiple STM evidences for the existence of topological surface states in {\gamma}-PtBi2. We observe not only the step-edge and screw dislocation induced quasiparticle interference fringes, originating from the electron scatterings between the Fermi arcs of {\gamma}-PtBi2, but also the back-scattering prohibition related to the spin-flip process, which is the direct evidence for the topological nature of the surface states. Moreover, we demonstrate that the topological surface states are precisely located over a narrow energy range near the Fermi level, within which sharply enhanced intensity and slow spatial decay of quasiparticle interference are observed.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Observation of unexpected band splitting and magnetically-induced band structure reconstruction in TbTi$_3$Bi$_4$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
Yevhen Kushnirenko, Lin-Lin Wang, Xiaoyi Su, Benjamin Schrunk, Evan O’Leary, Andrew Eaton, P. C. Canfield, Adam Kaminski
The magnetic Kagome materials are a promising platform to study the interplay between magnetism, topology, and correlated electronic phenomena. Among these materials, the RTi3Bi4 family received a great deal of attention recently because of its chemical versatility and wide range of magnetic properties. Here, we use angle-resolved photoemission spectroscopy measurements and density functional theory calculations to investigate the electronic structure of TbTi3Bi4 in paramagnetic and antiferromagnetic phases. Our experimental results show the presence of unidirectional band splitting of unknown nature in both phases. In addition, we observed a complex reconstruction of the band structure in the antiferromagnetic phase. Some aspects of this reconstruction are consistent with effects of additional periodicity introduced by the magnetic ordering vector, while the nature of several other features remains unknown.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
MatTools: Benchmarking Large Language Models for Materials Science Tools
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Siyu Liu, Jiamin Xu, Beilin Ye, Bo Hu, David J. Srolovitz, Tongqi Wen
Large language models (LLMs) are increasingly applied to materials science questions, including literature comprehension, property prediction, materials discovery and alloy design. At the same time, a wide range of physics-based computational approaches have been developed in which materials properties can be calculated. Here, we propose a benchmark application to evaluate the proficiency of LLMs to answer materials science questions through the generation and safe execution of codes based on such physics-based computational materials science packages. MatTools is built on two complementary components: a materials simulation tool question-answer (QA) benchmark and a real-world tool-usage benchmark. We designed an automated methodology to efficiently collect real-world materials science tool-use examples. The QA benchmark, derived from the pymatgen (Python Materials Genomics) codebase and documentation, comprises 69,225 QA pairs that assess the ability of an LLM to understand materials science tools. The real-world benchmark contains 49 tasks (138 subtasks) requiring the generation of functional Python code for materials property calculations. Our evaluation of diverse LLMs yields three key insights: (1)Generalists outshine specialists;(2)AI knows AI; and (3)Simpler is better. MatTools provides a standardized framework for assessing and improving LLM capabilities for materials science tool applications, facilitating the development of more effective AI systems for materials science and general scientific research.
Materials Science (cond-mat.mtrl-sci), Computation and Language (cs.CL), Databases (cs.DB)
27 pages, 23 figures
Beyond surfaces: quantifying internal radiative heat transport in dense materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
While phonons and electrons are well-established heat carriers in solids, photons are typically associated only with radiative transfer between surfaces. Yet for over 70 years, theorists have speculated that thermal photons could also conduct heat within dense, opaque materials – an idea that has remained unproven and unquantified. Here, we resolve this longstanding question by developing a first-principles framework that reveals and quantifies the internal radiative contribution to thermal conductivity in solids. By analyzing 15 crystalline materials, we uncover photon mean free paths (MFPs) ranging from $ \sim$ 100$ \mu$ m to over 1cm, with some materials exhibiting surprisingly large radiative thermal conductivity ($ \kappa_{\text{rad}}$ ). Contrary to common assumptions, we show that $ \kappa_{\text{rad}}$ can scale steeply with temperature (from $ T^{1}$ to $ T^{4}$ ), even as MFPs decrease (from $ T^{-0.3}$ to $ T^{-3}$ ). We also discover a robust link between photon MFP and phonon linewidths, revealing an unexpected interplay between radiative and phononic heat transport. Crucially, we establish a general formalism to calculate $ \kappa_{\text{rad}}$ across arbitrary sample thicknesses and surface emissivities – bridging ballistic and diffusive regimes. Our findings overturn long-held assumptions, uncover a missing channel of heat conduction, and provide a powerful new tool for thermal management in extreme environments.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
33 pages, 9 figures, 1 Table
Surface coupling of NV centers over nanoscale lengths
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Arsineh Apelian, Mariya Romanova, Vojtech Vlcek
Shallow nitrogen-vacancy (NV-) centers in diamond are among the most promising quantum sensors, offering high sensitivity and nanoscale spatial resolution. These systems are, however, prone to decoherence due to coupling with surface states. Here, we study sub-surface NV- centers embedded into large diamond slabs (8 nm) using various surface orientations (100 and 111) and terminations (hydrogen and nitrogen terminators) and compute the quasiparticle states of the defect. Our results show how dynamical charge fluctuations near the surface influence defect stability. We find that the (100) N-terminated surface introduces strong surface-state instabilities, while the (111) N-terminated surface provides a more favorable configuration. However, many-body calculations (within the GW approximation) reveal that defects placed shallower than ~ 4 nm are prone to surface-induced ionization. These findings establish an accurate theoretical limit on the minimum depth required for stable NV- centers, guiding the design of NV- based quantum sensors.
Materials Science (cond-mat.mtrl-sci)
Exploring the Interplay Between Formation Mechanisms and Luminescence of Lignin Carbon Quantum Dots from Spruce Biomass
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Jelena Papan Djaniš, Maja Szymczak, Jan Hočevar, Jernej Iskra, Boštjan Genorio, Darja Lisjak, Lukasz Marciniak, Karolina Elzbieciak-Piecka
This study investigates the intricate relationship between the formation mechanisms and luminescent properties of lignin-derived carbon quantum dots (LG-CQDs) synthesized from spruce biomass by hydrothermal treatment. A comprehensive understanding of LG-CQD structure and its photoluminescence requires insights into the native architecture of lignin and the distribution of its acidolysis-derived fragments. Research showed how these lignin-derived units interact with dopant molecules in three different approaches during synthesis, contributing to core and surface structures that govern the optical behavior. Our findings reveal a clear correlation between structural features and luminescent properties, emphasizing the role of surface chemistry in tuning emission characteristics. These insights provide a foundation for the rational design of LG-CQDs with tailored luminescent properties, advancing their potential applications in sustainable optoelectronics, sensing, and bioimaging.
Materials Science (cond-mat.mtrl-sci), Biological Physics (physics.bio-ph), Chemical Physics (physics.chem-ph)
Effects of Coupling Between Chiral Vibrations and Spins in Molecular Magnets
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
Aman Ullah, Sergey A. Varganov, Yafis Barlas
In single molecular magnets, chiral vibrations carrying vibrational angular momentum ($ \hat{L}^{\text{vib}}$ ) emerge due to the splitting of a doubly degenerate vibrational mode. Here, we identify a new type of effective spin-vibrational coupling responsible for lifting this degeneracy, which can facilitate optically selective excitations. In the presence of an external Zeeman field, this coupling breaks both inversion (in-plane parity) $ \mathcal{P}$ and time-reversal $ \mathcal{T}$ symmetries, imparting distinct geometric phases to the resulting dressed spin-vibronic states. The wave function of the spin-vibronic state is characterized by a $ \pi$ -Berry phase, which results in magneto-optical circular dichroism. This framework is validated using density functional theory and multi-reference \emph{ab initio} calculations on the Ce(trenovan) molecular magnet.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Pressure induced evolution of anisotropic superconductivity and Fermi surface nesting in a ternary boride
New Submission | Superconductivity (cond-mat.supr-con) | 2025-05-19 20:00 EDT
Subhajit Pramanick, Sudip Chakraborty, A. Taraphder
Using Migdal-Eliashberg theory implemented in Electron Phonon Wannier (EPW) code, we have investigated anisotropic superconductivity of a ternary boride $ \mathrm{Ta(MoB)_2}$ . The robust coupling between $ \mathrm{\sigma}$ -bonding states, primarily created by the d-orbitals of Mo atoms and the in-plane vibrations of Mo atoms, facilitates the generation of cooper pairs that make $ \mathrm{Ta(MoB)_2}$ a single-gap anisotropic superconductor with a critical temperature ($ \mathrm{T_c}\sim ) , 19.3$ K. A weak Fermi surface nesting and the low value of electron-phonon coupling cannot induce charge density wave instabilities, as evidenced by the lack of a significant peak in the real part of total Lindhard susceptibility and the absence of phonon softening. Furthermore, the system is readily tunable by hydrostatic pressure up to 76.69 GPa, owing to its low bulk modulus and negative formation energy. The persistent reduction in the density of states at the Fermi level, Fermi nesting and the stiffening of phonon modes leads to a diminution of superconductivity under pressure up to 59.71 GPa. At 76.69 GPa, a modification in the topology of the Fermi surface, namely a Lifshitz transition, occurs resulting in a sudden improvement in the nesting condition. This enhanced nesting, in turn, induces an abrupt stabilisation of superconductivity at 76.69 GPa, resulting in a V-shaped response to pressure.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
19 pages, 14 figures
A Non-Markovian Route to Coherence in Heterogeneous Diffusive Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-05-19 20:00 EDT
Temporal coherence-persistent alignment across time-can arise between agents with fundamentally distinct dynamics, a behavior that classical diffusion models (e.g., Brownian motion, fractional Brownian motion, generalized Langevin equation) are inherently limited in capturing, particularly under strong heterogeneity. We introduce the Coupled Memory Graph Process (CMGP), where dynamic interplay between internal memory and directed coupling enables synchronized behavior even in the absence of reciprocity. An active particle with long-range memory remains temporally coherent with a subdiffusive partner, despite mismatched scaling laws and asymmetric information flow. Bayesian optimization identifies a broad parameter regime supporting this phenomenon, characterized by a high State Persistence Index SPI. These results uncover a minimal mechanism for emergent coordination-a form of ghost coherence-that remains inaccessible to classical stochastic models, with implications for viscoelastic environments and heterogeneous active systems.
Statistical Mechanics (cond-mat.stat-mech)
Effect of crystallinity on spin-orbit torque in 5$\textit{d}$ iridium oxide IrO$_{2}$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Tetsuro Morimoto, Kohei Ueda, Junichi Shiogai, Takanori Kida, Masayuki Hagiwara, Jobu Matsuno
The 5$ \textit{d}$ transition-metal oxides provide an intriguing platform for generating an efficient spin current due to a unique electronic structure dominated by 5d electrons with strong spin-orbit coupling. Here, we report on the effect of crystallinity on current-driven spin-orbit torque (SOT) in binary 5$ \textit{d}$ iridium oxide IrO$ _{2}$ thin films by controlling amorphous, polycrystalline, and epitaxial states. By conducting harmonic Hall measurement in bilayers composed of ferromagnetic Co$ _{20}$ Fe$ _{60}$ B$ _{20}$ and IrO$ _{2}$ , we find that dampinglike (DL) SOT is larger than fieldlike SOT for all the samples. We also demonstrate that both electrical resistivity and the DL SOT efficiency increase in order of epitaxial, polycrystalline, and amorphous IrO$ _{2}$ . Despite their different electrical conductivities, spin Hall conductivities of the three states of the IrO$ _{2}$ layer are found to be nearly constant, which is consistent with the intrinsic regime of the spin Hall effect scaling relation. Our results highlight the important role that crystallinity plays in the spin-current generation, leading to the potential technological development of spintronic devices based on the 5$ \textit{d}$ transition-metal oxides.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
accepted
Universal scaling of segment fluctuations in polymer and chromatin dynamics
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-05-19 20:00 EDT
Kirill Polovnikov, Mehran Kardar
We demonstrate how center-of-mass (COM) motion influences polymer segment fluctuations. Cancellation of internal forces, together with spatially uncorrelated external noise, generally yields COM diffusivity scaling as $ 1/s$ with segment length $ s$ , regardless of fractal dimension, viscoelasticity, or activity. This introduces distinct dynamic scaling corrections to two-point fluctuations and quenched-induced tangential correlations, validated by theory, simulations, and chromatin imaging data. In the latter, the extracted dynamic exponent reveals topological constraints, thereby resolving the discrepancy between chromatin’s crumpled structure and its Rouse-like dynamics.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
An approach for thermal conductivity measurements in thin films: Combining localized surface topography, thermal analysis, and machine learning techniques
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Mohsen Dehbashi, Anna Kazmierczak-Balata, Jerzy Bodzenta
This study presents a comprehensive methodology for determining the thermal conductivity (TC) of materials with high reliability. The methodology addresses issues such as surface topographical variations and substrate interference by combining Scanning Thermal Microscopy (SThM) with machine learning (ML) models and normalization techniques. Micro- and nanostructural variations in thin films exacerbate measurement inconsistencies, reducing repeatability and reliability. These interconnected challenges highlight the need for a novel, flexible, and adaptive methodology that can comprehensively address the complexities of thin film characterization while maintaining accuracy and efficiency. In this approach, sample surface was divided into fine spatial grids for localized thermal and topographical measurements. A substrate-thickness factor (C factor) was introduced to account for thickness and substrate effects on thin film TC, and high-performance Random Forest regression was used to predict TC across a broad range of materials. The models were trained on a dataset of 2,352 measurements that covered a wide range of material properties and then validated with an additional 980 measurements. They achieved high predictive accuracy, with a $ R^2$ of 0.97886 during training and 0.96630 during testing. This approach addresses instrumental limitations and integrates experimental techniques with computational modeling, providing a scalable framework for a wide range of material science applications.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Novel high symmetry super-hard C48 and C32 allotropes with ana and ukc original topologies: Crystal chemistry and DFT investigations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Novel high symmetry body centered carbon allotropes: cubic C48 and tetragonal C32 are proposed with respective original ana and ukc topologies. Devised from crystal structure engineering, their ground state structures and energy derived physical properties were accurately derived based on quantum mechanics calculations within the density functional theory DFT. Both allotropes made of distorted tetrahedral C4 arrangements were found dense with rho larger than this http URL-3 that remain lower than diamond (rho = 3.50 this http URL-3). With cohesive albeit with metastable ground state structures, both allotropes show stability from the mechanical (elastic properties) and dynamic (phonons band structures) properties. Vickers hardness magnitudes HV(C48) =47 GPa and HV(C32) = 59 GPa point to super-hard materials. The electronic band structures range from large direct band gap close to 5 eV for C48 to indirect band gap close to 2.5 eV semi-conducting C32. Such findings of original allotropes with targeted physical properties are bound to enrich the field of research on carbon.
Materials Science (cond-mat.mtrl-sci)
14 page; 2 Tables; 4 Figures. arXiv admin note: substantial text overlap with arXiv:2504.15687, arXiv:2501.16820
Exploration of amorphous V$_2$O$_5$ as cathode for magnesium batteries
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Vijay Choyal, Debsundar Dey, Gopalakrishnan Sai Gautam
Development of energy storage technologies that can exhibit higher energy densities, better safety, and lower supply-chain constraints than the current state-of-the-art Li-ion batteries (LIBs) is crucial for our transition into sustainable energy use. In this context, Mg batteries (MBs) offer a promising pathway to design energy storage systems with superior volumetric energy densities than LIBs but require the development of positive electrodes (cathodes) exhibiting high energy and power densities. Notably, amorphous materials that lack long range order can exhibit `flatter’ potential energy surfaces than crystalline frameworks, possibly resulting in faster Mg$ ^{2+}$ motion. Here, we use a combination of ab initio molecular dynamics (AIMD), and machine learned interatomic potential (MLIP) based calculations to explore amorphous V$ _2$ O$ _5$ as a potential cathode for MBs. Using an AIMD-generated dataset, we train and validate moment tensor potentials that can accurately model amorphous (Mg)V$ _2$ O$ _5$ Due to the amorphization of V$ _2$ O$ _5$ , we observe a 10-14% drop in the average Mg intercalation voltage $ -$ but the voltage remains higher than sulfide Mg cathodes. Importantly, we find a $ \sim$ seven (five) orders of magnitude higher Mg$ ^{2+}$ diffusivity in amorphous MgV$ _2$ O$ _5$ than its crystalline version (thiospinel-Mg$ _x$ Ti$ _2$ S$ _4$ ), which is directly attributable to the amorphization of the structure. Also, we note the Mg$ ^{2+}$ motion in the amorphous structure is significantly cross-correlated at low temperatures, with the correlation decreasing with increase in temperature. Thus, our work highlights the potential of amorphous V$ _2$ O$ _5$ as a cathode that can exhibit both high energy and power densities, resulting in the practical deployment of MBs.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Inelastic tunneling into multipolaronic bound states in single-layer MoS$_2$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
Camiel van Efferen, Laura Pätzold, Tfyeche Y. Tounsi, Arne Schobert, Michael Winter, Yann in ‘t Veld, Mark Georger, Affan Safeer, Christian Krämer, Jeison Fischer, Jan Berges, Thomas Michely, Roberto Mozara, Tim Wehling, Wouter Jolie
Polarons are quasiparticles that arise from the interaction of electrons or holes with lattice vibrations. Though polarons are well-studied across multiple disciplines, experimental observations of polarons in two-dimensional crystals are sparse. We use scanning tunneling microscopy and spectroscopy to measure inelastic excitations of polaronic bound states emerging from coupling of non-polar zone-boundary phonons to Bloch electrons in n-doped metallic single-layer MoS$ _2$ . The latter is kept chemically pristine via contactless chemical doping. Tunneling into the vibrationally coupled polaronic states leads to a series of evenly spaced peaks in the differential conductance on either side of the Fermi level. Combining density functional (perturbation) theory with a recently developed ab initio electron-lattice downfolding technique, we show that the energy spacing stems from the longitudinal-acoustic phonon mode that flattens at the Brillouin zone edge and is responsible for the formation of stable multipolarons in metallic MoS$ _2$ .
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
16 pages, 14 figures
Thermodynamics of the $S=1/2$ maple-leaf Heisenberg antiferromagnet
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
The Heisenberg antiferromagnet on the maple-leaf lattice has recently gathered a great deal of attention. Competition between three non-equivalent bond interactions results in various ground-state quantum phases, the exact dimer-product singlet ground state being among them. The thermodynamic properties of this model are much less understood. We used high-temperature expansion up to the $ 18$ th order to study the thermodynamics of the $ S=1/2$ Heisenberg model on the uniform maple-leaf lattice with the ground state exhibiting a six-sublattice $ 120^{\circ}$ long-range magnetic order. Padé approximants allow us to get reliable results up to the temperatures of about $ T\approx 0.4$ . To study thermodynamics for arbitrary temperatures, we made the interpolation using the entropy method. Based on the analysis of close Padé approximants, we find ground-state energy $ e_{0}=-0.53064\ldots -0.53023$ in good agreement with numerical results. The specific heat $ c(T)$ has a typical maximum at rather low temperatures $ T\approx0.379$ and the uniform susceptibility $ \chi(T)$ at $ T\approx0.49$ . We also estimate the value of $ \chi(T)$ at zero temperature $ \chi_{0}\approx0.05\ldots0.06$ . The ground-state order manifests itself in the divergence of the so-called generalized Wilson ratio.
Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 5 figures
Trapping in a Casimir Force Set-Up Controlled by Solution Permeability
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
S. Pal, L. Inacio, L. M. Woods, U. De Giovannini, C. Persson, M. Boström
We have designed a system enabling tuning Casimir attraction/repulsion transitions between a polystyrene sphere attached to an atomic force microscope tip near a Teflon surface in a magnetic fluid mixture. Notably, the trapping distances can be changed by several orders of magnitude by changes in zero-frequency transverse electric contributions to the Casimir force. We demonstrate that this can be achieved via modifications in the average diameter for the magnetite particles while keeping the magnetite volume fractions fixed.
Materials Science (cond-mat.mtrl-sci)
6 pages, 4 figures, 1 table
Magnetotransport signatures of spin-orbit coupling in high-temperature cuprate superconductors
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
Aleix Barrera, Huidong Li, Thomas Gunkel, Jordi Alcalà, Silvia Damerio, Can Onur Avci, Anna Palau
Spin transport in superconductors offers a compelling platform to merge the dissipationless nature of superconductivity with the functional promise of spin-based electronics. A significant challenge in achieving spin polarisation in conventional superconductors stems from the singlet state of Cooper pairs, which exhibit no net spin. The generation of spin-polarised carriers, quasiparticles, or triplet pairs in superconductors has predominantly been realised in hybrid superconductor/ferromagnet systems through proximity-induced spin polarisation. Historically, cuprate superconductors have been characterised by strong electronic correlations but negligible spin-orbit coupling. Here, we report exceptionally large anisotropic magnetoresistance and a pronounced planar Hall effect arising near the superconducting phase transition in the prototypical high-temperature cuprate superconductor YBa2Cu3O7-x without using a proximity ferromagnet. These effects, unprecedented in centrosymmetric cuprates, emerge from spin-polarised quasiparticle transport mediated by strong spin-orbit coupling. By systematically tuning magnetic field strength, orientation, temperature, and doping, we show clear evidence of spin-orbit-driven transport phenomena in a material class long thought to lack such interactions. Our findings reveal an unexpected spin-orbit landscape in cuprates and open a route to engineer spintronic functionalities in high-temperature superconductors.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
Time-resolved electron dynamics in antiferromagnetic CoO(001) thin films
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Mathias Augstein, Friederike Wührl, Konrad Gillmeister, Cheng-Tien Chiang, Wolf Widdra
Ultrathin antiferromagnetic CoO(001)-(1x1) films of 2 and 4 monolayers (ML) on Ag(001) are investigated by time- and angle-resolved two-photon photoelectron (2PPE) spectroscopy. Pump-probe spectra show unoccupied states between 3.6 and 4.0,eV above the Fermi level ($ E_{F}$ ), which are identified as image potential states with momentum-dependent lifetimes between 12 to 20,fs. Electrons photoexcited across the band gap show lifetimes of 27,fs at the bottom of the Co $ 3d$ $ t_{2g}$ -derived conduction band minimum. This lifetime is much shorter than in conventional semiconductors. Our observations point either to strong electron correlation effects as has been demonstrated for NiO or to an ultrafast relaxation pathway via metallic substrate states.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
Space Group Equivariant Crystal Diffusion
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Rees Chang, Angela Pak, Alex Guerra, Ni Zhan, Nick Richardson, Elif Ertekin, Ryan P. Adams
Accelerating inverse design of crystalline materials with generative models has significant implications for a range of technologies. Unlike other atomic systems, 3D crystals are invariant to discrete groups of isometries called the space groups. Crucially, these space group symmetries are known to heavily influence materials properties. We propose SGEquiDiff, a crystal generative model which naturally handles space group constraints with space group invariant likelihoods. SGEquiDiff consists of an SE(3)-invariant, telescoping discrete sampler of crystal lattices; permutation-invariant, transformer-based autoregressive sampling of Wyckoff positions, elements, and numbers of symmetrically unique atoms; and space group equivariant diffusion of atomic coordinates. We show that space group equivariant vector fields automatically live in the tangent spaces of the Wyckoff positions. SGEquiDiff achieves state-of-the-art performance on standard benchmark datasets as assessed by quantitative proxy metrics and quantum mechanical calculations.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI)
Neutron Spin Resonance Near a Lifshitz Transition in Overdoped Ba${0.4}$K${0.6}$Fe$_2$As$_2$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-05-19 20:00 EDT
Yang Li, Dingsong Wu, Yingjie Shu, Bo Liu, Uwe Stuhr, Guochu Deng, Anton P. J. Stamp, Lin Zhao, Xingjiang Zhou, Shiliang Li, Amit Pokhriyal, Haranath Ghosh, Wenshan Hong, Huiqian Luo
Elucidating the relationship between spin excitations and fermiology is essential for clarifying the pairing mechanism in iron-based superconductors (FeSCs). Here, we report inelastic neutron scattering results on the hole overdoped Ba$ _{0.4}$ K$ _{0.6}$ Fe$ _2$ As$ _2$ near a Lifshitz transition, where the electron pocket at $ M$ point is nearly replace by four hole pockets. In the normal state, the spin excitations are observed at incommensurate wave vectors with chimney-like dispersions. By cooling down to the superconducting state, a neutron spin resonance mode emerges with a peak energy of $ E_r=$ 14-15 meV weakly modulated along $ L$ -direction. The incommensurability notably increases at low energies, giving rise to downward dispersions of the resonance mode. This behavior contrasts sharply with the upward dispersions of resonance observed in optimally doped Ba$ _{0.67}$ K$ _{0.33}$ Fe$ _2$ As$ _2$ contributed by the hole to electron scattering, but resembles with the cases in KFe$ _2$ As$ _2$ and KCa$ _2$ Fe$ _4$ As$ _4$ F$ _2$ where the fermiology are dominated by hole pockets. These results highlight the critical role of electronic structure modifications near the Fermi level, especially in governing interband scattering under imperfect nesting conditions, which fundamentally shape the spin dynamics of FeSCs.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 4 figures, Accepted by Chinese Physics Letters as Express Letter
Chinese Physics Letters 42, 067405 (2025)
Stabilization of a polar phase in WO3 thin films by epitaxial strain
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Ewout van der Veer, Martin F. Sarott, Jack T. Eckstein, Stijn Feringa, Dennis van der Veen, Johanna van Gent González, Majid Ahmadi, Ellen M. Kiens, Gertjan Koster, Bart J. Kooi, Michael A. Carpenter, Ekhard K. H. Salje, Beatriz Noheda
The introduction of new simple oxides that are CMOS-compatible constitutes an important step towards multifunctional oxide electronics. One such oxide, tungsten trioxide (WO3), has raised much interest as an electrode material. Here we reveal the presence of a previously unreported polar phase of WO3, obtained in thin films grown on YAlO3 substrates. The epitaxial strain stabilizes a triclinic phase, whose unit cell could be fully determined by means of large-scale reciprocal space mapping, rarely reported in thin films.
Unconventional strain accommodation mechanisms enable the triclinic phase to be stabilized up to unexpectedly large film thicknesses. The strain gradients around domain walls and local variations of octahedral tilts, observed by scanning transmission electron microscopy, could explain this behavior.
An in-plane striped domain pattern with needle-like bifurcations is visible in piezoresponse force microscopy maps, evidencing the polar nature of the films. Correspondingly, local modulations of the conductivity of the film are shown by conductive atomic force microscopy and scanning electron microscopy. These results open the possibility for adding functionalities to WO3-based devices by controlling conductivity and epitaxial strain.
Materials Science (cond-mat.mtrl-sci)
Submitted manuscript, 22 pages, 5 figures, 4 supplementary pages, 5 supplementary figures
Dimensionality dependence of diffusion-entropy scaling: Sensitivity to the diffusion mechanism
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-05-19 20:00 EDT
Nayana Venkatareddy, Mohd Moid, Prabal K. Maiti, Biman Bagchi
While entropy quantifies the volume of the accessible phase space, diffusion characterizes the rate of its exploration, capturing distinct yet interconnected aspects of a system’s dynamics. In this Letter, we employ computer simulations to independently compute D and S for Lennard-Jones (LJ) liquid and water in two and three dimensions, and for water also in one dimension, across a broad range of thermodynamic states. We observe that the ratio of diffusion coefficients between two states exhibits a nearly perfect exponential dependence on their entropy difference. For LJ liquids, the prefactor of the exponential shows a strong dimensionality dependence, consistent in trend but quantitatively different from theoretical predictions. In contrast, water displays a remarkably weak dimensionality dependence, deviating from theoretical expectations, which we attribute to the dominant role of jump diffusion. Surprisingly, the exponential diffusion-entropy relationship persists even when translational and rotational contributions to entropy are considered separately, underscoring the robustness of the D-S relation across different degrees of freedom.
Statistical Mechanics (cond-mat.stat-mech)
8 pages, 4 figures
Delayed Active Swimmer in a Velocity Landscape
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-05-19 20:00 EDT
Viktor Holubec, Giovanni Volpe, Frank Cichos
Self-propelled active particles exhibit delayed responses to environmental changes, modulating their propulsion speed through intrinsic sensing and feedback mechanisms. This adaptive behavior fundamentally determines their dynamics and self-organization in active matter systems, with implications for biological microswimmers and engineered microrobots. Here, we investigate active Brownian particles whose propulsion speed is governed by spatially varying activity landscapes, incorporating a temporal delay between environmental sensing and speed adaptation. Through analytical solutions derived for both short-time and long-time delay regimes, we demonstrate that steady-state density and polarization profiles exhibit maxima at characteristic delays. Significantly, we observe that the polarization profile undergoes sign reversal when the swimming distance during the delay time exceeds the characteristic diffusion length, providing a novel mechanism for controlling particle transport without external fields. Our theoretical predictions, validated through experimental observations and numerical simulations, establish time delay as a crucial control parameter for particle transport and organization in active matter systems. These findings provide insights into how biological microorganisms might use response delays to gain navigation advantages and suggest design principles for synthetic microswimmers with programmable responses to heterogeneous environments.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
6 pages, 4 figures
Angle-dependent resonant tunneling and thermoelectric energy management in a hybrid 1D-2D-1D semiconductor nanostructure
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
Xiaoguang Luo, Jiaming Wang, Jiawen Dai, Junqiang Zhang, Nian Liu
Low-dimensional semiconductors have been widely exploited in thermoelectric energy conversion for high efficiencies due to their suppressed lattice thermal conduction, sharply defined electronic density of states, and tunable energy-selective electron transmission. However, the widespread challenge of Fermi-level pinning or doping constraints limit precise control over thermoelectric energy management via chemical potential modulation. Here, we proposed an alternative strategy: leveraging angle-dependent electron incidence to dynamically manipulate electron transmission and heat transport, which was implemented theoretically in a two-dimensional InP/InAs/InP double-barrier heterostructure integrated with laterally one-dimensional electrodes. By combining the transfer matrix method and Landauer formalism, we demonstrated the angle-dependent resonant tunneling dynamics, tunable negative differential resistance effect, and near-Carnot limits in thermoelectric energy conversions. Angular modulation enables precise control over transmission resonances, facilitating dynamic transitions among thermoelectric regimes (power generation, cooling, and hybrid heating) without requiring extreme chemical potential shifts. This work establishes angularly resolved electron transmission as a versatile mechanism for on-chip thermal management and cryogenic applications, offering a pathway to circumvent material limitations in next-generation nanoelectronics and quantum devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
19 pages, 7 figures
Scalable thru-hole epitaxy of GaN through self-adjusting $h$-BN masks via solution-processed 2D stacks
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Jongwoo Ha, Minah Choi, Jieun Yang, Chinkyo Kim
Selective epitaxy on 2D-material masks is a promising pathway for achieving localized, defect-suppressed GaN growth, but conventional 2D transfer processes limit scalability and interface control. Here, we demonstrate a thru-hole epitaxy (THE) method that enables vertically connected and laterally overgrown GaN domains through a spin-coated, solution-processed stack of hexagonal boron nitride ($ h$ -BN) flakes. The disordered $ h$ -BN mask exhibits a self-adjusting structure during growth, which locally reconfigures to allow percolative precursor transport and coherent GaN nucleation beneath otherwise blocking layers. Comprehensive structural analyses using scanning electron microscopy, Raman mapping, and high-resolution transmission electron microscopy confirm both the presence of epitaxial GaN beneath the h-BN and suppression of threading dislocations. This strategy eliminates the need for patterned 2D mask transfers and demonstrates a scalable route to selective-area GaN growth on arbitrary substrates, relevant to future micro-LED and photonic integration platforms.
Materials Science (cond-mat.mtrl-sci)
Investigation of the spin dynamics of quantum spin dimers with Dzyaloshinsky-Moriya interaction
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
We investigate the ground state configuration and spin dynamics of a quantum spin spiral dimer when a magnetic field is applied to one of its constituent spins. By adiabatic changing the magnetic field, it is possible to change the non-magnetic ground state to a classical spiral state, which oscillates periodically to its inverted classical spiral state configuration. This oscillation can be halted at any time, leading to the possibility of manipulating the quantum state and the magnetic configuration of the spin dimer. Notably, this idea is not limited to spin dimers and can also be extended to quantum spin chains with an even number of spins.
Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 7 figures
On the Nature of the Fundamental Plasma Excitation in a Plasmonic Crystal
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
A. R. Khisameeva, A.Shuvaev, A. A. Zabolotnykh, A. S. Astrakhantseva, D. A. Khudaiberdiev, A. Pimenov, I. V. Kukushkin, V. M. Muravev
We report on the experimental study of the spectrum of plasma excitations in a plasmonic crystal fabricated from the two-dimensional electron system in an AlGaAs/GaAs semiconductor heterostructure. Our results reveal that the plasmonic crystal supports only a single fundamental plasma mode, challenging the current theoretical understanding that anticipates multiple modes. This unexpected finding is supported by comprehensive research on the mode frequency and relaxation as a function of the gate width across different plasmonic crystal periods. Furthermore, we develop an analytical approach that accurately describes the behavior of plasma excitations in plasmonic crystals, providing new insights into the fundamental physics of plasmonic systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 8 figures
Non-Ohmic behavior in (Bi$_{1-x}$Sb$_x$)$_2$Te$_3$ by Joule heating
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
Sofie Kölling, Daan H. Wielens, İnanç Adagideli, Alexander Brinkman
A prerequisite to using the net spin polarization generated by a source-drain bias in three-dimensional topological insulators for spintronic applications, is understanding how such a bias alters the transport properties of these materials. At low temperatures, quantum corrections can dominate the temperature dependence of the resistance. Although a DC bias does not break time-reversal symmetry and is therefore not expected to suppress quantum corrections, an increase of the electron temperature due to Joule heating can cause a suppression. This suppression at finite bias can lead to a non-Ohmic differential resistance in the three-dimensional topological insulator (Bi$ _{1-x}$ Sb$ _x$ )$ _2$ Te$ _3$ , consisting of a zero-bias resistance peak (from electron-electron interactions) and a high-bias background (from weak antilocalization). We show that the bias voltage dependence of quantum corrections can be mapped to the temperature dependence, while the heating effect on the lattice temperature remains small. When searching for non-Ohmic effects due to novel phenomena in three-dimensional topological insulators, Joule heating should not be overlooked.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 + 6 pages, 6 + 9 figures
Piezomagnetic effect in 5$d$ transition metal oxides Y$_2$Ir$_2$O$_7$ and Cd$_2$Os$_2$O$_7$ with all-in/all-out magnetic order
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
Hiroki Nanjo, Yoshinori Imai, Takuya Aoyama, Junichi Yamaura, Kenya Ohgushi
We investigated the piezomagnetic effect in pyrochlore-type oxides Y$ _2$ Ir$ _2$ O$ _7$ and Cd$ _2$ Os$ _2$ O$ 7$ , which show a non-coplanar magnetic structure called the all-in/all-out antiferromagnetic order at low temperatures. The all-in/all-out magnetic order can be viewed as a ferroic order of the $ xyz$ -type magnetic octupoles. We observed a linear development of magnetization with applying stress for both materials. We then estimated the powder-averaged piezomagnetic tensor at 50 K to be $ Q = 5.74 \times 10^{-6}$ $ \mu{\text{B}}$ /Ir$ \cdot$ MPa for Y$ _2$ Ir$ _2$ O$ 7$ , and $ Q = 3.49 \times 10^{-7}$ $ \mu{\text{B}}$ /Os$ \cdot$ MPa for Cd$ _2$ Os$ _2$ O$ _7$ . We discuss the microscopic mechanism of the piezomagnetic effect in terms of the stress-induced modification of the g-tensor anisotropy and Dzyaloshinskii-Moriya (D-M) interactions. This work paves the way for the further development of piezomagnetic materials using a strategy based on magnetic multipoles.
Strongly Correlated Electrons (cond-mat.str-el)
Simultaneous probes of pseudogap and disorder by hard x-ray photoemission applied for a candidate thermoelectric Al-Pd-Ru quasicrystal
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
N. U. Sakamoto, G. Nozue, H. Fujiwara, Y. Torii, M. Sakaguchi, T. D. Nakamura, T. Kiss, H. Sugawara, S. Tanaka, Y. Iwasaki, Y. Niwa, A. Ishikawa, T. D. Yamamoto, R. Tamura, A. Yasui, A. Sekiyama
The bulk electronic structure of Al-Pd-Ru quasicrystal (QC) have been investigated by hard X-ray photoemission spectroscopy (HAXPES). We have found an intrinsic pseudogap structure in which the spectral weight in the vicinity of the Fermi level (E_F) is remarkably suppressed at any photon energy. The valence-band HAXPES spectra and the asymmetry of the core-level peaks indicate a contribution of the Al sites to the electronic structure in the vicinity of E_F with less contributions from the Pd and Ru sites. The disorder effects are found in the core-level lineshapes of the Al-Pd-Ru QC, of which the widths are much broader than those of the other reference crystalline solids with less disorder.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn), Other Condensed Matter (cond-mat.other), Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 8 figures
Charge redistribution among copper and oxygen orbitals in the normal state of the Emery model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
G. L. Reaney, N. Kowalski, A.-M. S. Tremblay, G. Sordi
Unraveling the behavior of the electrons in the copper-oxygen planes of cuprate superconductors remains a challenge. Here we examine the electronic charge redistribution among planar copper and oxygen orbitals and the charge gap using the Emery model in the normal state, solved with cellular dynamical mean-field theory at finite temperature. We quantify the charge redistribution as a function of the onsite Coulomb repulsion on the copper orbitals, the bare copper-oxygen energy difference, and the hole or electron doping. We find that the position relative to the metal to insulator boundary of the Zaanen-Sawatzky-Allen diagram determines the charge redistribution among copper and oxygen orbitals. For a fixed bare Cu-O energy difference, an increase in the Cu electron repulsion leads to a transfer of the electronic charge from Cu to O orbitals. For a fixed charge gap size of the undoped state, as the system evolves from a charge-transfer to a Mott-Hubbard regime, the electronic charge is transferred from Cu to O orbitals. Our findings posit the Coulomb repulsion and the bare charge-transfer energy as key drivers of the microscopic process of charge redistribution in the CuO$ _2$ plane. They quantify the anticorrelation between the charge gap size and oxygen hole content. They show that for fixed band-structure parameters, the charge gap and the charge redistribution between Cu and O orbitals provide a way to understand observed trends in cuprates.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
13 pages, 10 figures
Numerical Block-Diagonalization and Linked Cluster Expansion for Deriving Effective Hamiltonians: Applications to Spin Excitations
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
We present a non-perturbative framework for deriving effective Hamiltonians that describe low-energy excitations in quantum many-body systems. The method combines block diagonalization based on the Cederbaum–Schirmer–Meyer transformation with the numerical linked-cluster (NLC) expansion. A key feature of the approach is a variational criterion that uniquely determines the unitary transformation by minimizing the transformation of the state basis within the low-energy subspace. This criterion also provides a robust guideline for selecting relevant eigenstates, even in the presence of avoided level crossing and mixing induced by particle-number-nonconserving interactions. We demonstrate the method in two quantum spin models: the one-dimensional transverse-field Ising model and the two-dimensional Shastry–Sutherland model, relevant to SrCu$ _2$ (BO$ _3$ )$ _2$ . In both cases, the derived effective Hamiltonians faithfully reproduce the structure and dynamics of magnon and triplon excitations, including the emergence of topological band structures. The block diagonalization enables quantum fluctuations to be incorporated non-perturbatively, while the NLC expansion systematically accounts for finite-size corrections from larger clusters. This approach naturally generates long-range effective interactions near criticality, even when the original Hamiltonian includes only short-range couplings. The proposed framework provides a general and computationally feasible tool for constructing physically meaningful effective models across a broad range of quantum many-body systems.
Strongly Correlated Electrons (cond-mat.str-el)
13 pages, 8 figures
Chemically active droplets in crowded environments
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-05-19 20:00 EDT
Jacques Fries, Roxanne Berthin, Chengjie Luo, Marie Jardat, David Zwicker, Vincent Dahirel, Pierre Illien
Biomolecular condensates are essential for cellular organization and result from phase separation in systems far from thermodynamic equilibrium. Among various models, chemically active droplets play a significant role, consisting of proteins that switch between attractive and repulsive states via nonequilibrium chemical reactions. While field-based simulations have provided insights into their behavior, these coarse-grained approaches fail to capture molecular-scale effects, particularly in crowded cellular environments. Macromolecular crowding, a key feature of intracellular organization, strongly influences molecular transport within condensates, yet its quantitative impact remains underexplored. This study investigates the interplay between chemically active droplets and crowders by using particle-based models, that provide molecular insight, and a field-based model, that complements this picture. Surprisingly, crowding reduces droplet size while expanding the overall dense phase volume, challenging equilibrium-based expectations. This effect arises from the interplay between depletion interactions, diffusion hindrance, and nonequilibrium particle fluxes. Our findings provide a step towards a more comprehensive understanding of chemically active droplets in complex, realistic cellular environments.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
Emergent Thermalization Thresholds in Unitary Dynamics of Inhomogeneously Disordered Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-05-19 20:00 EDT
Soumya Kanti Pal, C L Sriram, Shamik Gupta
Inspired by the avalanche scenario for many-body localization (MBL) instability, we reverse the conventional set-up and ask whether a large weakly-disordered chain can thermalize a smaller, strongly-disordered chain when the composite system evolves unitarily. Using transport as a dynamical probe, we identify three distinct thermalization regimes as a function of the disorder strength of the smaller chain: (i) complete thermalization with self-averaging at weak disorder, (ii) realization-dependent thermalization with strong sample-to-sample fluctuations at intermediate disorder, and (iii) absence of thermalization at strong disorder. We find that the non-self-averaging regime broadens with the size of the weakly-disordered chain, revealing a nuanced interplay between disorder and system size. These results highlight how inhomogeneous disorder can induce emergent thermalization thresholds in closed quantum systems, providing direct access to disorder regimes where thermalization or its absence can be reliably observed.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Quantum Physics (quant-ph)
14 pages, 7 figures
Anisotropic magnetic phase diagrams, tricriticality, and spin-reorientation in high-pressure grown SmCrO$_3$ single crystals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
Ning Yuan, Erik Walendy, Nour Maraytta, Waldemar Hergett, Luca Bischof, Michael Merz, Rüdiger Klingeler
SmCrO$ 3$ single crystals were successfully grown utilizing the high-pressure optical floating-zone method and their crystal structure, magnetization behavior, and magnetic phase diagrams were thoroughly investigated. Magnetic studies were conducted for fields applied along all principal crystallographic directions, with measurements taken at temperatures as low as 0.4 K and magnetic fields up to 14 T. The single crystal growth parameters are reported and the orthorhombic structure with the centrosymmetric space group $ Pbnm$ is confirmed. Long-range order of the Cr$ ^{3+}$ and Sm$ ^{3+}$ magnetic sublattices evolves at $ T{\rm N}$ = 192 K and $ T_{\rm N2}$ =3 K, respectively. In contrast to previous studies on polycrystals our single crystal data imply a discontinuous and one-step spin-reorientation (SR) of net magnetic moments $ \tilde{M}$ from the $ c$ axis into the $ ab$ plane at zero magnetic field at $ T_{\rm SR}$ =33 K. Its discontinuous nature is maintained if $ B$ is applied $ ||c$ axis but tricritical behavior and a triple point is found for $ B||a$ axis. While our data are consistent with the magnetic representation $ \Gamma_4$ for $ T > T_{\mathrm {SR}}$ , the size and in-plane direction of the observed net magnetic moment disagree to previously proposed spin configurations, i.e., $ \Gamma_1$ and $ \Gamma_2$ , for the spin-reoriented phases. In general, our high-quality single crystals enable us to revisit the phase diagram and to clarify the complex magnetism in SmCrO3 arising from the interplay of anisotropic 3$ d$ and 4$ f$ magnetic sublattices.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
Resistivity of non-Galilean invariant two dimensional Dirac system
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-05-19 20:00 EDT
V. M. Kovalev, M. V. Entin, Z. D. Kvon, A. D. Levin, V. A. Chitta, G. M. Gusev, N. N. Mikhailov
We revisited the influence of electron-electron scattering on the resistivity of a two-dimensional system with linear spectrum. In conventional systems with parabolic spectrum, where Umklapp scattering is either prohibited or ineffective due to small Fermi surface, particle-particle scattering does not contribute to conductivity because it does not change the total momentum. However, within the framework of Boltzmann kinetic model, we demonstrate that electron-electron scattering in Dirac systems can significantly contribute to conductivity, producing distinct temperature-dependent corrections: a T\textsuperscript{4} behavior at low temperatures and T\textsuperscript{2} dependence at moderate temperatures. While the predicted T\textsuperscript{4} scaling is not observed experimentally – likely suppressed by dominant weak localization effects – the T\textsuperscript{2} scaling is clearly confirmed in our measurements. Specifically, temperature-dependent resistivity data from gapless single-valley HgTe quantum well exhibit T\textsuperscript{2} corrections, which align well with theoretical predictions. Thus, we challenge the paradigm that T\textsuperscript{2} term in resistivity is absent in single-band 2D metals.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
14 pages, 8 figures
Phys. Rev.Lett. 134, 196303 (2025)
Linear Magnetoresistance and Anomalous Hall Effect in the Superconductor NiBi$_{3}$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-05-19 20:00 EDT
Gabriel Sant’ana, Jully Paola Peña Pacheco, David Mockli, Fabiano Mesquita da Rosa, Sergio Garcia Magalhães, Paulo Pureur, Milton A. Tumelero
The NiBi$ _{3}$ compound exhibits an intriguing interplay of superconductivity, magnetism, and topology. While the possibility of unconventional superconductivity involving magnetic interactions has been previously discussed and dismissed, the topological character of its electronic structure has only recently gained attention. Here, we report experimental evidence of unconventional magnetic ordering in high-quality single crystals of NiBi$ _{3}$ , revealed through detailed magnetotransport measurements. The magnetoresistance shows a distinct temperature dependence, combining a classical Lorentz-like component with a linear-in-field contribution. Moreover, anomalous Hall effect signals persist down to the superconducting transition and vanish above 75 K. These results indicate that spin textures significantly influence charge transport in NiBi$ _{3}$ , pointing to a compensated magnetic background intertwined with its topological electronic structure. Our findings underscore the complex and multifaceted nature of this material.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
7 pages, 4 figures, plus 3 figures in the SM material at the ending of the document
Born-limit scattering and pair-breaking crossover in d-wave superconductivity of (TMTSF)2ClO4
New Submission | Superconductivity (cond-mat.supr-con) | 2025-05-19 20:00 EDT
Shota Yano, Kazumi Fukushima, Katsuki Kinjo, Soichiro Yamane, Le Hong Hoàng To, Pascale Senzier, Cécile Mézière, Shamashis Sengupta, Claire A Marrache-Kikuchi, Denis Jerome, Shingo Yonezawa
In the quasi-one-dimensional organic unconventional superconductor (TMTSF)2ClO4, the randomness of the non-centrosymmetric ClO4 anions can be experimentally controlled by adjusting the cooling rate through the anion-ordering temperature. This feature provides a unique opportunity to study disorder effects on unconventional superconductivity in great detail. We here report on measurements of the electronic specific heat of this system, performed under various cooling rates. The evolution of the residual density of states indicates that the ClO4 randomness works as Born-limit pair breakers, which, to our knowledge, has never been clearly identified in any unconventional superconductors. Furthermore, detailed analyses suggest a peculiar crossover from strong unitarity scattering due to molecular defects toward the Born-limit weak scattering due to borders of ordered regions. This work supports the d-wave nature of pairing in (TMTSF)2ClO4 and intends to provide an experimental basis for further developments of pair-breaking theories of unconventional superconductors where multiple electron scattering mechanisms coexist.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 5 figures
Theory of Quasi-Statically Screened Electron-Polar Optical Phonon Scattering
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Yuji Go, Rajeev Dutt, Neophytos Neophytou
The scattering of electrons with polar optical phonons (POP) is an important mechanism that limits electronic transport and determines electron mobility in polar materials. This is typically a stronger mechanism compared to non-polar acoustic and optical phonon scattering, and of similar strength to the Coulomb ionized impurity scattering. At high densities, on the other hand, the cloud of charge carriers screens the dipoles that are responsible for POP scattering, and weakens the electron-POP scattering strength. However, in contrast to ionized impurity scattering, for which the well-known Brooks-Herring equation provides the scattering rates with the effect of screening included, for scattering with POP there is no such closed-form mathematical expression. In this work, we derive such an expression based on Fermi’s Golden Rule, which would prove particularly useful in understanding electronic transport in complex crystal and complex band structure materials, in which electron-POP scattering could dominate electronic transport.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
18 pages, 11 figures
Lattice models with subsystem/weak non-invertible symmetry-protected topological order
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-05-19 20:00 EDT
We construct a family of lattice models which possess subsystem non-invertible symmetry-protected topological (SPT) order and analyze their interface modes protected by the symmetry, whose codimension turns out to be more than one. We also propose 2+1d lattice models which belong to two different weak SPT phases distinguished by a combination of translational symmetry and non-invertible symmetry. We show that the interface between them exhibits an exotic Lieb-Schultz-Mattis anomaly coming from the symmetry which cannot be written as a direct product of an internal symmetry and the lattice translational symmetry.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
53 pages, 4 figures
Combined Experimental and Computational Analysis of Lithium Diffusion in Isostructural Pair VNb9O25 and VTa9O25
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Manish Kumar, Md Abdullah Al Muhit, CJ Sturgill, Nima Karimitari, John T. Barber, Hunter Tisdale, Morgan Stefik, Hans-Conrad zur Loye, Christopher Sutton
Wadsley-Roth crystal structures are an attractive class of materials for batteries because lithium diffusion is facilitated by the ReO3-like block structure with electron transport enabled by edge-sharing along shear planes. However, clear structure-property relationships remain limited, making it challenging to develop improved materials. Here, the first lithiation of VTa9O25 is reported, enabling a direct isostructural comparison with the better-known VNb9O25. These materials have similar unit cell volumes and atomic radii yet exhibit different voltage windows, C-rate dependent capacities, and transport metrics. Time-dependent overpotential analysis reveals ionic diffusion as the primary bottleneck to high rate-performance in both cases, however, the lithium diffusivity for VNb9O25 was an order of magnitude faster than that for VTa9O25. These experimental trends aligned well with density functional theory calculations combined with molecular dynamics that show a factor of six faster diffusion in VNb9O25. Nudged elastic band calculations of the probable hopping pathways indicate that VNb9O25 consistently exhibits a lower activation barrier for lithium diffusion. Bader charge analysis reveals a larger net charge on Li in VNb9O25 due to the higher electronegativity of Nb which stabilizes the transition state and lowers the barrier. This stabilization arises from the stronger Coulombic interaction between Li and its coordinated O-environment. These materials behave similarly upon lithiation wherein the lattice vectors (corresponding to the block plane) increase until about 50% lithiation and then decrease. However, the electronic structure differs, indicating that VNb9O25 undergoes a insulator to metal transition at a lower state of charge compared with VTa9O25. Overall, this work establishes the role of the cation (Nb or Ta) on the electronic and transport properties during lithiation.
Materials Science (cond-mat.mtrl-sci)
The fate of the Fermi surface coupled to a single-wave-vector cavity mode
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-05-19 20:00 EDT
Bernhard Frank, Michele Pini, Johannes Lang, Francesco Piazza
The electromagnetic field of standing-wave or ring cavities induces a spatially modulated, infinite-range interaction between atoms in an ultracold Fermi gas, with a single wavelength comparable to the Fermi length. This interaction has no analog in other systems of itinerant particles and has so far been studied only in the regime where it is attractive at zero distance. Here, we fully solve the problem of competing instabilities of the Fermi surface induced by single-wavelength interactions. We find that while the density-wave (superradiant) instability dominates on the attractive side, it is absent for repulsive interactions, where the competition is instead won by non-superradiant superfluid phases at low temperatures, with Fermion pairs forming at both vanishing and finite center-of-mass momentum. Moreover, even in the absence of such symmetry-breaking instabilities, we find the Fermi surface to be always nontrivially deformed from an isotropic shape. We estimate this full phenomenology to be within reach of dedicated state-of-the-art experimental setups.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph), Quantum Physics (quant-ph)
Main text: 8 pages, 5 figures Supplementary material: 17 pages, 8 figures
Magnetostriction and Temperature Dependent Gilbert Damping in Boron Doped Fe${80}$Ga${20}$ Thin Films
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-05-19 20:00 EDT
Zhixin Zhang, Jinho Lim, Haoyang Ni, Jian-Min Zuo, Axel Hoffmann
Magnetic thin films with strong magnetoelastic coupling and low Gilbert damping are key materials for many magnetoelectric devices. Here, we investigated the effects of boron doping concentration on magnetostriction and temperature dependent Gilbert damping in magnetron sputtered (Fe$ _{80}$ Ga$ _{20}$ )$ _{1-x}$ B$ {x}$ films. A crystalline to amorphous structural transition was observed for a boron content near 8% and coincided with a decrease in coercivity from 76 Oe to 3 Oe. A 10% doping concentration is optimal for achieving both large magnetostriction of 48.8 ppm and low Gilbert damping of $ 6 \times 10^{-3}$ . The temperature dependence of the damping shows an increase at low temperatures with a peak around 40 K and we associate the relative increase $ \Delta\alpha/\alpha{RT}$ with magnetoelastic contributions to the damping, which has a maximum of 55.7% at 8% boron. An increase in the inhomogeneous linewidth broadening was observed in the structural transition regime at about 8% boron concentration. This study suggests that incorporation of glass forming elements, in this case boron, into Fe$ _{80}$ Ga$ _{20}$ is a practical pathway for simultaneously achieving enhanced magnetoelastic coupling and reduced Gilbert damping.
Materials Science (cond-mat.mtrl-sci)
19 pages, 7 figures
Exactly solvable many-body dynamics from space-time duality
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-05-19 20:00 EDT
Bruno Bertini, Pieter W. Claeys, Tomaž Prosen
Recent years have seen significant advances, both theoretical and experimental, in our understanding of quantum many-body dynamics. Given this problem’s high complexity, it is surprising that a substantial amount of this progress can be ascribed to exact analytical results. Here we review dual-unitary circuits as a particular setting leading to exact results in quantum many-body dynamics. Dual-unitary circuits constitute minimal models in which space and time are treated on an equal footings, yielding exactly solvable yet possibly chaotic evolution. They were the first in which current notions of quantum chaos could be analytically quantified, allow for a full characterisation of the dynamics of thermalisation, scrambling, and entanglement (among others), and can be experimentally realised in current quantum simulators. Dual-unitarity is a specific fruitful implementation of the more general idea of space-time duality in which the roles of space and time are exchanged to access relevant dynamical properties of quantum many-body systems.
Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th), Mathematical Physics (math-ph), Chaotic Dynamics (nlin.CD), Quantum Physics (quant-ph)
65 pages, 20 figures