CMP Journal 2025-08-11
Statistics
Nature: 1
Nature Nanotechnology: 5
Nature Physics: 2
Nature Reviews Materials: 1
arXiv: 52
Nature
Catalytic enantioselective synthesis of alkylidenecyclopropanes
Original Paper | Asymmetric catalysis | 2025-08-10 20:00 EDT
Jonathan C. Golec, Dong-Hang Tan, Ken Yamazaki, Eveline H. Tiekink, Kirsten E. Christensen, Trevor A. Hamlin, Darren J. Dixon
The enantioselective construction of small ring carbocycles provides organic chemists with an enduring challenge.1 Despite their commercial importance, enantioselective synthetic routes towards alkylidenecyclopropanes (ACPs), a class of small ring carbocycles, remain underdeveloped.2,3 Importantly, ACPs can be converted into cyclopropanes, a common feature in drug molecules (e.g. Nirmatrelvir, 1),4 as well as both naturally occurring and synthetic agrochemicals (e.q. permethrin 2).5,6 We now describe the facile synthesis of highly enantioenriched alkylidenecyclopropanes through the use of a bifunctional iminophosphorane (BIMP) catalysed, stereo-controlled, strain-relieving deconjugation. Small modifications to the basic catalyst system were used to broaden the scope of the reaction to substrates containing ester, amide, phosphine oxide, and ketone functionalities. Through the design of a suitable substrate and re-tuning of the catalyst’s iminophosphorane moiety, the transformation was effectively applied to the synthesis of a single stereoisomer of the commonplace insecticide permethrin as well as a range of cyclopropane-based insecticide cores. State-of-the-art computational studies were performed to provide detailed insight into the mechanistic pathway and origin of both diastereo- and enantioselectivities.
Asymmetric catalysis, Asymmetric synthesis, Synthetic chemistry methodology, Stereochemistry
Nature Nanotechnology
Limiting endosomal damage sensing reduces inflammation triggered by lipid nanoparticle endosomal escape
Original Paper | Drug delivery | 2025-08-10 20:00 EDT
Serena Omo-Lamai, Yufei Wang, Manthan N. Patel, Aleksa Milosavljevic, Daniel Zuschlag, Subhajit Poddar, Jichuan Wu, Liuqian Wang, Fengyi Dong, Carolann Espy, Aparajeeta Majumder, Eno-Obong Essien, Mengwen Shen, Breana Channer, Tyler E. Papp, Michael Tobin, Rhea Maheshwari, Sumin Jeong, Sofia Patel, Anit Shah, Shruthi Murali, Liam S. Chase, Marco E. Zamora, Mariah L. Arral, Oscar A. Marcos-Contreras, Jacob W. Myerson, Christopher A. Hunter, Dennis Discher, Peter J. Gaskill, Andrew Tsourkas, Vladimir R. Muzykantov, Igor Brodsky, Sunny Shin, Kathryn A. Whitehead, Hamideh Parhiz, Jeremy Katzen, Jonathan J. Miner, Dirk Trauner, Jacob S. Brenner
Lipid nanoparticles (LNPs) have emerged as the dominant platform for RNA delivery, but they induce severe inflammation. Here we show that LNPs’ hallmark feature, endosomal escape, which is necessary for RNA expression, also triggers inflammation by causing endosomal membrane damage. Large, irreparable, endosomal holes are recognized by cytosolic proteins called galectins, which regulate downstream inflammation. We find that inhibition of galectins abrogates LNP-associated inflammation, both in vitro and in vivo. Moreover, we show that a unique class of ionizable lipids can create smaller endosomal holes, reparable by the endosomal sorting complex required for transport (ESCRT) pathway. Such lipids can produce high expression from cargo messenger RNA with minimal inflammation. Finally, we show that both galectin inhibition or ESCRT-recruiting ionizable lipids allow for treatment of highly inflammatory disease models by therapeutic mRNAs. These strategies should lead to safer non-inflammatory LNPs that can be generally used to treat inflammatory diseases.
Drug delivery, Nanoparticles
Ultrabroadband nonlinear Hall rectifier using SnTe
Original Paper | Electronic devices | 2025-08-10 20:00 EDT
Fanrui Hu, Pengnan Zhao, Lihuan Yang, Shishun Zhao, Jiayu Lei, Weijian Li, Jiamin Lai, Zhonghai Yu, Hanbum Park, Chengquan Wong, Raghav Sharma, Goki Eda, Shengyuan A. Yang, Xiaohong Xu, Fei Wang, Hyunsoo Yang
The rapid expansion of self-powered electronics in the Internet of Things, 6G communication and millimetre-wave systems calls for rectifiers capable of operating across ultrabroadband frequencies and at extremely low input power levels. However, conventional rectifiers based on semiconductor junctions face fundamental limitations such as parasitic capacitance and threshold voltages, preventing effective operation under broadband and ambient radio-frequency conditions. Here we present an ultrabroadband, zero-bias rectifier based on the nonlinear Hall effect in wafer-scale (001)-oriented topological crystalline insulator SnTe thin film. This material exhibits a large second-order conductivity of ~0.004 Ω⁻1 V⁻1, surpassing that of other wafer-scale materials. The nonlinear Hall effect arises primarily from a Berry curvature dipole, evidenced by angular-resolved transport measurements and first-principles calculations. The device demonstrates rectification from 23 MHz to 1 THz, with sensitivity down to -60 dBm in key radio-frequency bands, without any external bias. Rectified output power is scalable through series- and parallel-array topologies and can be enhanced using rectenna designs. As a proof of concept, we achieve the wireless powering of a thermistor using harvested radio-frequency energy, validating the potential of this material platform and nonlinear Hall effect for next-generation energy-autonomous microsystems.
Electronic devices, Topological matter
Compact polyethylenimine-complexed mRNA vaccines
Original Paper | Drug delivery | 2025-08-10 20:00 EDT
Jorge Moreno Herrero, Theo B. Stahl, Stephanie Erbar, Konrad Maxeiner, Anne Schlegel, Tijana Bacic, Jens Schumacher, Leide P. Cavalcanti, Martin A. Schroer, Dmitri I. Svergun, Ugur Sahin, Heinrich Haas
Here we describe formulations comprising individual, polymer-complexed self-amplifying RNA (saRNA) molecules, designed for vaccination against infectious diseases and other prophylactic and therapeutic applications. When exposed to a large excess of the cationic polymer polyethylenimine (PEI), the single saRNA molecules in solution reorganize from an extended to a globular organization, characterized by a high packing density, low polymer mass fraction and, consequently, a very small size of the polyplex nanoparticles of about 30 nm. This format of PEI-complexed saRNA exhibits enhanced biological activity in comparison with previously described saRNA/PEI formulations, both in vitro and in vivo. In vaccination models, relevant immune responses at lower doses are achieved, offering potential advantages for practical use. We found that the single PEI-complexed RNA molecules are also present in conventional formulations to some degree. The direct correlation between the single-molecule fraction with activity suggests that it is this format that predominantly contributes to activity in the different formulation types. Complexation is driven by mechanisms of self-assembly between oppositely charged polyelectrolytes, making this protocol broadly applicable to various cationic polymers and RNA constructs. With their small size and good stability in biofluids, these compacted RNA molecules are also promising for the systemic delivery of genetic material to compartments that are difficult to reach with larger particles.
Drug delivery, Nanoparticles
Systemic reprogramming of tumour immunity via IL-10-mRNA nanoparticles
Original Paper | Biomedical engineering | 2025-08-10 20:00 EDT
Chuang Liu, Xiangang Huang, Kok-Siong Chen, Sihan Xiong, Alexey V. Yaremenko, Xueyan Zhen, Xinru You, Filippo Rossignoli, Yi Tang, Seyoung Koo, Wei Chen, Na Kong, Tian Xie, Khalid Shah, Wei Tao
Daily subcutaneous injections of recombinant interleukin-10 (IL-10) demonstrated encouraging but preliminary efficacy in certain tumour types during early phase clinical trials. However, these antitumour effects were not consistently replicated in larger trials, probably due to insufficient intratumoural recombinant IL-10 accumulation, which ultimately restricted clinical benefit. Here we show that intravenous injections of IL-10 messenger RNA (mRNA) nanoparticles (IL-10-mRNA@NPs) induce potent immune surveillance across diverse preclinical tumour models and mitigate systemic toxicities. In particular, IL-10-mRNA@NPs sustain in situ IL-10 production within tumours, promoting substantial infiltration and proliferation of cytotoxic T cells, activation and maturation of dendritic cells, and an augmented expression of major histocompatibility complex class I molecules in immunosuppressive orthotopic early stage hepatocellular carcinoma tumours. Moreover, in mice with orthotopic middle-to-late-stage hepatocellular carcinoma tumours, combining IL-10-mRNA@NPs with immune checkpoint blockades results in 43% of mice showing complete tumour eradication and a sixfold increase in median survival compared with mice treated with immune checkpoint blockades alone. Furthermore, this combination induces long-lasting antitumour immune memory, conferring 100% protection against tumour rechallenges. The intravenous IL-10-mRNA@NPs strategy may have potential to overcome the challenges associated with recombinant IL-10 in clinical trials across a broad spectrum of immunosuppressive tumours.
Biomedical engineering, Drug delivery, Nanoparticles, Nanostructures
Annexin A1 mRNA-loaded liposomes alleviate acute pancreatitis by suppressing STING pathway and promoting efferocytosis in macrophages
Original Paper | Biomedical engineering | 2025-08-10 20:00 EDT
Haizong Fang, Peidong You, Shengzhe Lin, Yuwei Wu, Jiajing Lin, Zelin Hou, Feihong Liang, Changgan Chen, Zhiyuan Wang, Linlin Chen, Shihan Zhang, Xiaolan Chen, Kui Zhao, Fengchun Lu, Minggui Pan, Yundong Zhou, Chengliang Yin, João Conde, Heguang Huang, Yu Pan
Acute pancreatitis (AP) is associated with high mortality rates and is characterized by increased cell death of acinar cells, with the premature release and activation of digestive enzymes. In its acute phase, AP is accompanied by increased efferocytosis, to clear phagocytic apoptotic cells; annexin A1 (Anxa1) is key to efferocytosis, but its role in AP is still unknown. Here we show that Anxa1 deficiency abrogates the efferocytosis of pancreatic macrophages, resulting in the accumulation of apoptotic acinar cells and necrosis. Moreover, we showed that nano-liposomes loaded with Anxa1 mRNA alleviate AP pathology by suppressing the cGAMP-cGAS-STING pathway and restoring efferocytosis in macrophages. Our results reveal the crucial function of Anxa1 in the efferocytosis of macrophages during AP and illustrate a novel nanotechnology treatment approach for AP that may be of potential therapeutic value in humans.
Biomedical engineering, Nanoparticles
Nature Physics
Strongly interacting Hofstadter states in magic-angle twisted bilayer graphene
Original Paper | Electronic properties and materials | 2025-08-10 20:00 EDT
Minhao He, Xiaoyu Wang, Jiaqi Cai, Jonah Herzog-Arbeitman, Ran Peng, Takashi Taniguchi, Kenji Watanabe, Ady Stern, B. Andrei Bernevig, Matthew Yankowitz, Oskar Vafek, Xiaodong Xu
Magic-angle twisted bilayer graphene hosts a variety of strongly correlated states at partial fillings of its flat bands. In a magnetic field, these flat bands evolve into a Hofstadter spectrum renormalized by strong Coulomb interactions. Here we study the interacting Hofstadter states that spontaneously form within the topological magnetic sub-bands of an ultraclean magic-angle twisted bilayer graphene device, including symmetry-broken Chern insulator states and fractional quantum Hall states. The observed symmetry-broken Chern insulator states form a cascade, with their Chern numbers mimicking the main sequence of correlated Chern insulators. The fractional quantum Hall states form in a Jain sequence. However, they disappear at high magnetic field, in contrast to conventional fractional quantum Hall states that strengthen with increasing magnetic field. We reveal a magnetic-field-driven phase transition from composite fermion phases to a dissipative Fermi liquid. Our theoretical analysis of the magnetic sub-bands hosting the fractional quantum Hall states predicts non-uniform quantum geometric properties far from the lowest Landau level. This points towards a more natural interpretation of these states as in-field fractional Chern insulators of the magnetic sub-bands.
Electronic properties and materials, Quantum Hall
Optomechanical control of long-lived bulk acoustic phonons in the quantum regime
Original Paper | Nonlinear optics | 2025-08-10 20:00 EDT
Hilel Hagai Diamandi, Yizhi Luo, David Mason, Tevfik Bulent Kanmaz, Sayan Ghosh, Margaret Pavlovich, Taekwan Yoon, Ryan Behunin, Shruti Puri, Jack G. E. Harris, Peter T. Rakich
High-fidelity quantum optomechanical control of a mechanical oscillator requires the ability to perform efficient, low-noise operations on long-lived phononic excitations. Microfabricated high-overtone bulk acoustic wave resonators (μHBARs) support high-frequency mechanical modes above 10 GHz with coherence times exceeding one millisecond. Here we demonstrate a μHBAR-based cavity optomechanical system that permits quantum optomechanical control of individual high-coherence phonon modes. We perform laser cooling of the phonon modes from an occupation of approximately 22 phonons to fewer than 0.4, corresponding to laser-based ground-state cooling of a mechanical object with a mass of 7.5 μg. During the cooling process we do not observe any absorption-induced heating, demonstrating the resilience of the HBAR optomechanical systems against parasitic heating. Our work demonstrates that μHBARs are promising as the basis for quantum optomechanical systems with robustness to decoherence that is necessary for efficient, low-noise photon-phonon conversion.
Nonlinear optics, Quantum mechanics, Quantum optics
Nature Reviews Materials
Synthetic methods for high-entropy nanomaterials
Review Paper | Materials chemistry | 2025-08-10 20:00 EDT
Nabojit Kar, Sara E. Skrabalak
‘High entropy’ has become a key concept in materials science over the past two decades, with this concept more recently extended to nanomaterials. High-entropy materials, characterized by the incorporation of five or more principal elements in nearly equal proportions, leverage entropy to promote the formation of compositionally complex single-phase materials rather than phase-segregated alternatives. The extensive compositional space of high-entropy nanomaterials, as well as their distinct structural and catalytic properties, has garnered considerable interest. The synthesis of high-quality single-phase high-entropy nanoparticles is important to fully realizing their potential to drive innovation, and numerous synthetic routes exist. Top-down methods begin with bulk high-entropy materials and break them down into nanosized structures, whereas bottom-up strategies start from atoms and build nanomaterials through nucleation and growth. In this Review, we categorize and compare the synthetic methods for high-entropy alloy and high-entropy intermetallic nanoparticles. Our discussion reveals that colloidal synthesis offers excellent control over the composition, size and shape of high-entropy nanoparticles while also providing pathways to metastable states that are not always accessible by other methods.
Materials chemistry, Nanoparticles
arXiv
Rolling at right angles: magnetic anisotropy enables dual-anisotropic active matter
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-11 20:00 EDT
Eavan Fitzgerald, Cécile Clavaud, Debasish Das, Isaac C.D. Lenton, Scott R. Waitukaitis
We report on an experimental active matter system with motion restricted to four cardinal directions. Our particles are magnetite-doped colloidal spheres driven by the Quincke electrorotational instability. The absence of a magnetic field $ (|\mathbf{B}|=0)$ leads to circular trajectories interspersed with short spontaneous runs. Intermediate fields $ (|\mathbf{B}|\lesssim 20~\text{mT})$ linearize the motion orthogonal to the field – the axial mode. At high magnetic fields, we observe the surprising emergence of a second linearization parallel to the field – the tumbling mode, distinct from the first orthogonal linearization. With numerical simulations, we show that this behavior can be explained by anisotropic magnetic susceptibility.
Soft Condensed Matter (cond-mat.soft)
Quantum criticality and nonequilibrium dynamics on a Lieb lattice of Rydberg atoms
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-11 20:00 EDT
Mark R. Hirsbrunner, Milan Kornjača, Rhine Samajdar, Siva Darbha, Majd Hamdan, Jan Balewski, Ermal Rrapaj, Sheng-Tao Wang, Daan Camps, Fangli Liu, Pedro L. S. Lopes, Katherine Klymko
Neutral-atom quantum simulators offer a promising approach to the exploration of strongly interacting many-body systems, with applications spanning condensed matter, statistical mechanics, and high-energy physics. Through a combination of quantum experiments, numerical calculations, and analytical methods, we demonstrate a rich set of phenomena accessible on such quantum simulators by studying an array of Rydberg atoms placed on the Lieb lattice. First, we map out the ground states and phase diagram of the system, identifying a range of density-wave-ordered phases,and find excellent agreement between theory and experiment. Allowing for local control of the detuning field thereafter, we discover a quantum analog of the classical liquid–vapor transition and probe its underlying hysteretic dynamics. Furthermore, we study out-of-equilibrium quantum quenches and observe anomalously slow relaxation dynamics arising from kinetic constraints. These results highlight how geometric control offered by neutral-atom simulators can extend the frontiers of programmable quantum matter, enabling access to complex phases, metastability, and thermalization dynamics in many-body quantum systems.
Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el), Atomic Physics (physics.atom-ph), Quantum Physics (quant-ph)
Universal Magnetocaloric Effect near Quantum Critical Point of Magnon Bose-Einstein Condensation
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-11 20:00 EDT
Junsen Xiang, Enze Lv, Qinxin Shen, Cheng Su, Xuetong He, Yinghao Zhu, Yuan Gao, Xin-Yang Liu, Dai-Wei Qu, Xinlei Wang, Xi Chen, Qian Zhao, Haifeng Li, Shuo Li, Jie Yang, Jun Luo, Peijie Sun, Wentao Jin, Yang Qi, Rui Zhou, Wei Li, Gang Su
Bose-Einstein condensation (BEC), a macroscopic quantum phenomenon arising from phase coherence and bosonic statistics, has been realized in quantum magnets. Here, we report the observation of a universal magnetocaloric effect (MCE) near a BEC quantum critical point (QCP) in copper sulfate crystal ($ CuSO_4 \cdot 5H_2O$ ). By conducting magnetocaloric and nuclear magnetic resonance measurements, we uncover a field-driven BEC QCP, evidenced by the universal scaling law $ T_c \propto (B_c - B)^{2/3}$ and the perfect data collapse of the magnetic Grüneisen ratio. Thermal excitation triggers a dimensional crossover to a 1D quantum-critical regime, where the MCE scaling strictly matches the universality class of 1D Fermi gases. Notably, the quantum-critical MCE enables cooling down to 12.8 mK without helium-3, with very fast thermal relaxation rate that is critical for high cooling power. This work demonstrates the universal MCE in magnon BEC systems, using a common copper sulfate compound as a paradigmatic example, and paves the way for next-generation sub-Kelvin cooling.
Strongly Correlated Electrons (cond-mat.str-el)
20 pages, 15 figures
Evaluating Universal Machine Learning Force Fields Against Experimental Measurements
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Sajid Mannan, Vaibhav Bihani, Carmelo Gonzales, Kin Long Kelvin Lee, Nitya Nand Gosvami, Sayan Ranu, Santiago Miret, N M Anoop Krishnan
Universal machine learning force fields (UMLFFs) promise to revolutionize materials science by enabling rapid atomistic simulations across the periodic table. However, their evaluation has been limited to computational benchmarks that may not reflect real-world performance. Here, we present UniFFBench, a comprehensive framework for evaluating UMLFFs against experimental measurements of ~1,500 carefully curated mineral structures spanning diverse chemical environments, bonding types, structural complexity, and elastic properties. Our systematic evaluation of six state-of-the-art UMLFFs reveals a substantial reality gap: models achieving impressive performance on computational benchmarks often fail when confronted with experimental complexity. Even the best-performing models exhibit higher density prediction error than the threshold required for practical applications. Most strikingly, we observe disconnects between simulation stability and mechanical property accuracy, with prediction errors correlating with training data representation rather than the modeling method. These findings demonstrate that while current computational benchmarks provide valuable controlled comparisons, they may overestimate model reliability when extrapolated to experimentally complex chemical spaces. Altogether, UniFFBench establishes essential experimental validation standards and reveals systematic limitations that must be addressed to achieve truly universal force field capabilities.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
Dynamics and rupture of doped Motility Induced Phase Peparation
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-11 20:00 EDT
Rodrigo Fernández-Quevedo García, Enrique Chacón, Pedro Tarazona, Chantal Valeriani
Adding a small amount of passive (Brownian) particles to a two-dimensional dense suspension of repulsive active Brownian particles does not affect the appearance of a motility-induced phase separation into a dense and a dilute phase, caused by the persistence of the active particles’ direction of motion. Unlike a purely active suspension, the dense slab formed in an elongated system of a passive-active mixture may show, over long periods of time, a stable and well-defined propagation of the interfaces, because of the symmetry breaking caused by the depletion of passive particles on one side of the slab. We investigate these dynamical structures via average density profile calculations, revealing an asymmetry between the two interfaces, and enabling a kinetic analysis of the slab movement. The apparent movement of the dense slab is not a pure source/sink effect, nor a rigid displacement of all the particles, but a self-sustained combination of both effects. Furthermore, we analyse the specific fluctuations that produce, cancel and abruptly reverse the slab motion.
Soft Condensed Matter (cond-mat.soft)
Soft Matter, 2025,21, 5413-5422
A free fermions in disguise model with claws
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
Kohei Fukai, István Vona, Balázs Pozsgay
Recently, several spin chain models have been discovered that admit solutions in terms of “free fermions in disguise.” A graph-theoretical treatment of such models was also established, giving sufficient conditions for free fermionic solvability. These conditions involve a particular property of the so-called frustration graph of the Hamiltonian, namely that it must be claw-free. Additionally, one set of sufficient conditions also requires the absence of so-called even holes. In this paper, we present a model with disguised free fermions where the frustration graph contains both claws and even holes. Special relations between coupling constants ensure that the free fermionic property still holds. The transfer matrix of this model can be factorized in a special case, thereby proving the conjectured free fermionic nature of a special quantum circuit published recently by two of the present authors. This is the first example of free fermions in disguise with both claws and even holes simultaneously.
Statistical Mechanics (cond-mat.stat-mech), Mathematical Physics (math-ph), Exactly Solvable and Integrable Systems (nlin.SI)
46 pages, 18 figures
Observing Differential Spin Currents by Resonant Inelastic X-ray Scattering
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
Yanhong Gu, Joseph Barker, Jiemin Li, Takashi Kikkawa, Fernando Camino, Kim Kisslinger, John Sinsheimer, Lukas Lienhard, Jackson J. Bauer, Caroline A. Ross, Dmitri N. Basov, Eiji Saitoh, Jonathan Pelliciari, Gerrit E. W. Bauer, Valentina Bisogni
Controlling spin currents, i.e., the flow of spin angular momentum, in small magnetic devices is the principal objective of spin electronics, a main contender for future energy efficient information technologies. Surprisingly, a pure spin current has never been measured directly since the associated electric stray fields and/or shifts in the non-equilibrium spin-dependent distribution functions are too small for conventional experimental detection methods optimized for charge transport. Here we report that resonant inelastic x-ray scattering (RIXS) can bridge this gap by measuring the spin current carried by magnons – the quanta of the spin wave excitations of the magnetic order – in the presence of temperature gradients across a magnetic insulator. This is possible due to the sensitivity of the momentum- and energy-resolved RIXS intensity to minute changes in the magnon distribution under non-equilibrium conditions. We use the Boltzmann equation in the relaxation time approximation to extract transport parameters, such as the magnon lifetime at finite momentum, essential for the realization of magnon spintronics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
Rydberg Exciton Dynamics in the Blockade Regime of Cu2O
New Submission | Other Condensed Matter (cond-mat.other) | 2025-08-11 20:00 EDT
Gillian E. Minarik, Eric A. Arsenault, Vinícius da Silveira Lan Avelar, Taketo Handa, X.-Y. Zhu
Hosting giant Rydberg excitons with principal quantum numbers up to n = 30, cuprous oxide (Cu2O) provides a rare solid-state setting for exploring Rydberg physics, as exemplified by the blockade effect. Here we access the strongly interaction regime at high excitation densities (10^14-10^16/cm^3) and resolve the corresponding blockade dynamics for n = 2-7 using time-resolved spectroscopy. We find that Rydberg blockades are primarily governed by resonant dipolar interactions and that exciton recombination is coupled to the blockade itself. These findings demonstrate the potential for manipulating Rydberg exctions in the strongly interacting blockade regime in a solid state system.
Other Condensed Matter (cond-mat.other)
15 pages 4 figures. 3 Supporting Figures
Simulation of a generalized asset exchange model with investment and income mechanisms
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
Jan Tobochnik, Harvey Gould, William Klein
An agent-based model of the economy is generalized to incorporate investment and guaranteed income mechanisms in addition to the exchange and distribution mechanisms considered in earlier models. We find realistic wealth distributions and realistic values of the Gini coefficients and the Pareto index. We also show that although the system reaches a steady state, the system is not in thermal equilibrium. The nonequilibrium behavior is associated with the multiplicative noise generated by the investment mechanism.
Statistical Mechanics (cond-mat.stat-mech)
22 pages, 12 figures
Emerging ultra-wide band gap semiconductors for future high-frequency electronics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Emily M. Garrity, Theodora Ciobanu, Andriy Zakutayev, Vladan Stevanovic
To meet the growing demands of advanced electronic systems, next-generation power and RF semiconductor devices must operate efficiently at higher power levels and switching frequencies while remaining compact. Current state-of-the-art GaN semiconductor devices alone cannot meet all these demands. Emerging ultra-wide band gap (UWBG) alternatives like diamond, BN, AlN, and Ga2O3, face significant challenges including limited wafer availability, doping difficulties, and thermal management constraints. Herein we conduct a high-throughput computational screening for new semiconductors for high-frequency electronics. In our analysis we compute the modeled Johnson and Baliga high-frequency figures of merit in combination with thermal conductivity to assess their potential for RF and power devices. We show that there are plenty of alternative materials to explore and conclude by discussing dopability and synthesis of select candidate materials. This study lays the foundation for discovering new semiconductors that can push the boundaries of performance in applications ranging from EV chargers and solid-state transformers to sub-THz communications and advanced radar technologies.
Materials Science (cond-mat.mtrl-sci)
Perspective, 6 pages, 3 figures
Unexpectedly large entropic barrier controls bond rearrangements in vitrimers
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-11 20:00 EDT
Shinian Cheng, Lilliana Rey, Beibei Yao, Ivan Popov, Alexei P. Sokolov
Vitrimers are a relatively new class of polymeric materials containing associative covalent dynamic bonds that make them recyclable by design. However, the fundamental mechanisms controlling their viscoelastic properties remain poorly understood. Our detailed studies of relaxation dynamics and viscoelastic behavior of model vitrimers revealed that the density of dynamic covalent crosslinks has no influence on chain dynamics (beyond a weak change in the glass transition temperature), yet it strongly affects the linear viscoelasticity of vitrimers. Increasing the crosslink density induces a sol-gel transition consistent with predictions of classical gelation theory, demonstrating its applicability to vitrimers. Remarkably, the temperature-dependent analysis of the bond rearrangement time reveals an unexpectedly large negative activation entropy in the transition state that strongly slows down the bond exchange process despite its relatively low activation enthalpy. This insight explains the unusual long timescale for bond rearrangement in vitrimers and highlights the significance of entropy in controlling the viscoelasticity of dynamic covalent networks.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
23 pages with Supplementary Materials, 4 figures in Main text, 4 figures in Supplementary Materials, 50 references
Fusion and Fission of Particle-like Chiral Nematic Vortex Knots
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-11 20:00 EDT
Darian Hall, Jung-Shen Benny Tai, Louis H. Kauffman, Ivan I. Smalyukh
Vortex knots have been seen decaying in many physical systems. Here we describe topologically protected vortex knots, which remain stable and undergo fusion and fission while conserving a topological invariant analogous to that of baryon number. While the host medium, a chiral nematic liquid crystal, exhibits intrinsic chirality, cores of the vortex lines are structurally achiral regions where twist cannot be defined. We refer to them as “dischiralation” vortex lines, in analogy to dislocations and disclinations in ordered media where, respectively, positional and orientational order is disrupted. Fusion and fission of these vortex knots, which we reversibly switch by electric pulses, vividly reveal the physical embodiments of knot theory’s concepts like connected sums of knots. Our findings provide insights into related phenomena in fields ranging from cosmology to particle physics and can enable applications in electro-optics and photonics, where such fusion and fission processes can be used for controlling light.
Soft Condensed Matter (cond-mat.soft)
Spin-resolved Josephson diode effect through strongly spin-polarized conical magnets
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-11 20:00 EDT
Danilo Nikolić, Niklas L. Schulz, Alexander I. Buzdin, Matthias Eschrig
We present a theoretical study of the spin-resolved Josephson diode effect in junctions comprising strongly spin-polarized conical magnets (FM) coupled to singlet superconductors (SC). The system is treated by making use of the Gor$ ^\prime$ kov and quasiclassical Green$ ^\prime$ s function methods. Modeling the SC/FM interfaces as spin-dependent $ \delta$ -potentials, we apply our model to an SC/FM/SC junction and account for the Josephson current-phase relation (CPR). The nontrivial coupling between the spin bands in the conical magnet gives rise to a strong Josephson diode effect with an efficiency greater than 40%. The effect essentially depends on the quantum spin-geometric phase that enters the Josephson CPR in a very similar manner to the superconducting phase difference. The former is generated non-locally by the intrinsically noncoplanar spin arrangement of the conical magnet, which breaks the time-reversal and inversion symmetries. Strong spin polarization and a helical pitch of the conical magnet comparable to the superconducting coherence length are essential for the effect. We perform a harmonic analysis of the Josephson CPR and interpret the effect in terms of coherent transfer of multiple equal-spin triplet Cooper pairs across the conical magnet.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
18 pages, 7 figures
Isolated spin ladders in Ln$_2$Ti$9$Sb${11}$ (Ln:La-Nd) metals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-11 20:00 EDT
Brenden R. Ortiz, Heda Zhang, Karolina Gornicka, Matthew S. Cook, Suchismita Sarker, Satoshi Okamoto, Jiaqiang Yan
Here we present the discovery and characterization of a series of antimonides Ln$ _2$ Ti$ _9$ Sb$ _{11}$ (Ln: La–Nd) which exhibit well-isolated, $ n=2$ rare-earth spin ladders. We discuss the structure of the new compounds, with a particular focus on the magnetic Ln spin ladders. Nd$ _2$ Ti$ _9$ Sb$ _{11}$ and Ce$ _2$ Ti$ _9$ Sb$ _{11}$ exhibit antiferromagnetic interactions and a well-defined doublet ground state, whereas Pr$ _2$ Ti$ _9$ Sb$ _{11}$ exhibits a weakly magnetic singlet ground state. Nd$ _2$ Ti$ _9$ Sb$ _{11}$ is a poor metal with an electrical resistivity of 0.1m$ \Omega$ -cm at 300K and weak temperature dependence. The thermal conductivity along the ladder exhibits significant field dependence even at 40K, considerably higher than the magnetic ordering temperature of 1.1K. Compared to compounds with transition metal spin ladders, the rare-earth elements impart much lower energy scales, making these compounds highly tunable with external stimuli like magnetic fields. The diverse magnetism of the rare-earth ions and RKKY interactions further contribute to the potential for a wide array of rich magnetic ground states, positioning these materials as a rare example of an inorganic square spin-ladder platform.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
Structural and Optical Properties of Crystal Ion Sliced BaTiO$_3$ Thin Films
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Hossein Esfandiar, Fatemeh Abtahi, Trevor G. Vrckovnik, G. Quyet Ngo, Rene Heller, Ulrich Kentsch, Fabian Ganss, Stefan Facsko, Uta Lucchesi, Stephan Winnerl, Falk Eilenberger, Dennis Arslan, Sebastian W. Schmitt
Barium titanate (BaTiO$ _3$ ) is a compelling material for integrated photonics due to its strong electro-optic and second-order nonlinear properties. Crystal Ion Slicing (CIS) presents a scalable and CMOS-compatible route for fabricating thin BaTiO$ _3$ films; however, ion implantation during CIS introduces lattice damage that can degrade structural and optical performance. In this study, we demonstrate that post-slicing thermal annealing effectively restores the structural integrity and optical quality of CIS-processed BaTiO$ _3$ flakes. Raman spectroscopy confirms the recovery of crystallinity, while second-harmonic generation (SHG) microscopy reveals systematic reorientation of ferroelectric domains and restoration of the associated second-order nonlinear susceptibility tensor $ X^{(2)}$ . Notably, SHG signals persist even in regions with weak Raman signatures, indicating that long-range ferroelectric order can survive despite partial lattice disruption. Optical measurements show that the linear dispersion of annealed CIS flakes closely matches that of bulk BaTiO$ _3$ , validating their suitability for photonic integration. Together, these results qualify CIS - combined with thermal annealing - as a viable and scalable manufacturing strategy for high-quality BaTiO$ _3$ -on-insulator (BTOI) platforms, enabling advanced integrated photonic devices for modulation, frequency conversion, and quantum optics.
Materials Science (cond-mat.mtrl-sci), Optics (physics.optics)
Quantum Hall Resistance and Quantum Hall Plateaus from Edge State Quantization
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
Despite the extensive literature on the quantum Hall effect (QHE), a direct derivation of the phenomenological formula $ \rho_{xy} = h/e^2\nu$ from first principles has remained elusive. In this work, we revisit the Landau and Landauer-Büttiker formalisms and impose hard-wall boundary conditions on the wavefunction, an essential but often overlooked constraint. This condition quantizes the guiding center position and the longitudinal wave number $ k_x$ , leading naturally to a discrete number of edge states without invoking energy bending. We derive the Hall resistance directly and recover the standard result $ \rho_{xy} = h/e^2\nu$ , along with an explicit expression for the filling factor $ \nu$ in terms of the Fermi energy and magnetic field. The resulting resistance steps reproduce the observed QHE plateaus and match experimental data without fitting parameters.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
5 pages, 3 figure
Dimensionality-induced dynamical phase transition in the large deviation of local time density for Brownian motion
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
We study the fluctuation properties of the local time density, $ {\rho _T} = \frac{1}{T}\int_0^T {\delta ( {r(t) - 1} )} dt$ , spent by a $ d$ -dimensional Brownian particle at a spherical shell of unit radius, where $ r(t)$ denotes the radial distance from the particle to the origin. In the large observation time limit, $ T \to \infty$ , the local time density $ \rho_T$ obeys the large deviation principle, $ P(\rho _T= \rho) \sim e^{-T I(\rho)}$ , where the rate function $ I(\rho)$ is analytic everywhere for $ d\leq 4$ . In contrast, for $ d>4$ , $ I(\rho)$ becomes nonanalytic at a specific point $ \rho=\rho_c^{(d)}$ , where $ \rho_c^{(d)}=d(d-4)/(2d-4)$ depends solely on dimensionality. The singularity signals the occurrence of a first-order dynamical phase transition in dimensions higher than four. Such a transition is accompanied by temporal phase separations in the large deviations of Brownian trajectories. Finally, we validate our theoretical results using a rare-event simulation approach.
Statistical Mechanics (cond-mat.stat-mech)
10 pages, 5 figures
Topological Defect Formation Beyond the Kibble-Zurek Mechanism in Crossover Transitions with Approximate Symmetries
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
Peng Yang, Chuan-Yin Xia, Sebastian Grieninger, Hua-Bi Zeng, Matteo Baggioli
The formation of topological defects during continuous second-order phase transitions is well described by the Kibble-Zurek mechanism (KZM). However, when the spontaneously broken symmetry is only approximate, such transitions become smooth crossovers, and the applicability of KZM in these scenarios remains an open question. In this work, we address this problem by analyzing both a weakly coupled Ginzburg-Landau model and a strongly coupled holographic setup, each featuring pseudo-spontaneous breaking of a global U(1) symmetry. In the slow quench regime, we observe a breakdown of the universal power-law scaling predicted by the Kibble-Zurek Mechanism. Specifically, the defect density acquires an exponential correction dependent on the quench rate, following a universal form dictated by the source of explicit symmetry breaking. Although these dynamics extend beyond the scope of the traditional KZM, we demonstrate that a generalized framework, that incorporates the effects of explicit symmetry breaking into the dynamical correlation length, remains valid and accurately captures the non-equilibrium defect formation across the entire range of quench rates.
Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
v1: comments welcome
Revisiting $μ$SR Studies of Ion Dynamics in the Light of Extended Kubo-Toyabe Model
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Takashi U. Ito, Ryosuke Kadono
The dynamical Kubo-Toyabe (dKT) function is extended to describe the spin relaxation under the coexisting dynamical and static internal magnetic fields. A detailed re-evaluation of the previous $ \mu^\pm$ SR data in Na$ _x$ CoO$ _2$ using this function disfavors the conventional interpretation based on sodium-ion diffusion and instead supports the $ \mu^+$ self-diffusion scenario. This also resolves the long-standing inconsistencies in the dKT-function-based $ \mu$ SR studies on ion diffusion from the viewpoint of classical over-barrier-jump mechanism.
Materials Science (cond-mat.mtrl-sci)
6 pages, 3 figures
Photodynamic melting of phase-reversed charge stripes and enhanced condensation
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-11 20:00 EDT
Jianhao Sun, Richard T. Scalettar, Rubem Mondaini
The interplay between charge stripes and pairing is a longstanding point of scrutiny in a broad class of unconventional superconductors since, in some cases, it is unclear whether their intertwining benefits the ensuing superfluidity. Experiments that explore the out-of-equilibrium dynamics of these systems try to tip the balance in favor of one phase or the other by selective coupling to relevant modes. Leveraging the fact that competition between stripes and pairing is not exclusive to fermionic systems, we explore the photoirradiation dynamics of interacting hardcore bosons, in which density wave phase-reversal melting gives rise to enhanced superfluid properties, quantified by the dynamic amplification of zero-momentum occupancy and charge stiffness. Our results, obtained using unbiased methods for an interacting system on a ladder geometry, demonstrate how one can engineer time-dependent perturbations to release suppressed orders, potentially providing insight into the underlying mechanism in related experiments.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
8+6 pages; 5+5 figures
Reconstructing Critical Current Density in Josephson Junctions with Phase Non-linearity
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-11 20:00 EDT
A. Kudriashov, R. A. Hovhannisyan, X. Zhou, L. Elesin, L. V. Yashina, K. S. Novoselov, D. A. Bandurin
In this Letter, we show that the standard Dynes-Fulton analysis, commonly used to reconstruct the critical current density from interference patterns, breaks down in Josephson junctions with nonlinear phase distributions, leading to non-physical artifacts. To address this, we developed a simple iterative reconstruction algorithm and validated it both numerically and experimentally using a planar Josephson junction model. Unlike conventional approaches based on the logarithmic Hilbert transform, the proposed method allows for incorporating prior knowledge about the system and addresses the fundamental issue of ambiguity in reconstructing the critical current density from interference patterns.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Vacuum Dealloyed Brass as Li-Metal Battery Current Collector: Effect of Zinc and Porosity
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Eric V Woods, Xinren Chen, Shaolou Wei, Alisson Kwiatkowski da Silva, Ayman A El-Zoka, J Manoj Prabhakar, Tim M Schwarz, Yongqiang Kang, Leonardo S Aota, Mahander P Singh, Katja Angenendt, Ozge Ozgun, Matic Jovivcevic-Klug, Patricia Jovivcevic-Klug, Christian Bross, Jian Liu, Rene de Kloe, Gerhard Dehm, Stefan Zaefferer, Yug Joshi, Baptiste Gault
“Anode-free” lithium-metal batteries promise significantly higher energy density than conventional graphite-based lithium-ion batteries; however, lithium dendrite growth can lead to internal short circuits with associated safety risks. While porous current collectors can suppress dendrite growth, optimal porosity and composition remain unknown. Here, we show that the temperature during vapor phase dealloying (VPD) of alpha-brass (Cu63Zn37) controls the surface Zn concentration, decreasing from 8 percent to below 1 percent from 500 to 800 degrees C. The surface composition is controlled by the temperature-dependent diffusion. A battery cell maintains greater than 90 percent Coulombic efficiency (CE) over 100 cycles when the Zn content is the lowest, whereas the higher-Zn samples degraded to approximately 70 percent CE. The difference in surface composition has hence dramatic effects on battery performance, and our results demonstrate how precise compositional control enables stable lithium-metal battery operation, establishing about 1 atomic percent surface Zn as optimal for preventing capacity fading and uniform lithium plating, while establishing predictive relationships between processing temperature and surface composition. This work provides design rules for multifunctional current collectors and demonstrates scalable VPD production for next-generation batteries.
Materials Science (cond-mat.mtrl-sci)
58 pages, 6 main figures, 20 SI figures; main text and supplementary information included in a single PDF
Magic Entropy in Hybrid Spin-Boson Systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-11 20:00 EDT
Samuel Crew, Ying-Lin Li, Heng-Hsi Li, Po-Yao Chang
We introduce entropic measures to quantify non-classical resource in hybrid spin-boson systems. We discuss the stabilizer Rényi entropy in the framework of phase space quantisation and define an analogous hybrid magic entropy and a mutual magic entropy that capture the distribution of quantum magic across spin and bosonic subsystems. We use these entropic measures to demonstrate two key phenomena: the detection of the superradiant phase transition in the Dicke model and the dynamics of magic in the Jaynes-Cummings model following a quench. We develop a Monte Carlo numerical scheme to enable practical computation in many-body examples.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
15 pages, 3 figures
Analysis of Spin Current Generation by Elastic Waves in $f$-wave Altermagnets
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
Ken Uchino, Yuuki Ogawa, Satoru Hayami
We theoretically investigate the mechanism of spin current generation induced by elastic waves in nonrelativistic magnets referred to as altermagnets. By analyzing an $ f$ -wave altermagnet formed by a three-sublattice noncollinear antiferromagnetic structure breaking the spatial inversion symmetry on a two-dimensional triangular lattice within the linear response theory, we show that the nonrelativistic antisymmetric spin-split band structure can give rise to spin current generation when either longitudinal or transverse elastic wave is applied. We find that the momentum dependence of the antisymmetric spin splitting leads to a characteristic direction-dependent spin current response. We also compare the present nonrelativistic magnetic-order-driven mechanism with the relativistic one in a nonmagnetic Rashba system. These findings highlight the potential of invesion-symmetry-breaking altermagnets as a spin current generator driven by elasticity without relying on the relativistic spin-orbit coupling.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 7 figures
Scalable High-Temperature Superconducting Diodes in Intrinsic Josephson Junctions
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-11 20:00 EDT
Zihan Wei, Youkai Qiao, Yang-Yang Lyu, Da Wang, Tianyu Li, Leonardo Rodrigues Cadorim, Ping Zhang, Wen-Cheng Yue, Dingding Li, Ziyu Song, Zixi Wang, Yunfan Wang, Milorad V. Milošević, Yong-Lei Wang, Huabing Wang, Peiheng Wu
Superconducting diodes, characterized by nonreciprocal supercurrent transport, offer transformative opportunities for ultra-low-power circuits. However, achieving reliable operation at temperatures above liquid nitrogen remains a major challenge, limiting their practical applicability. Here, we present a scalable strategy for high-temperature superconducting diodes based on intrinsic Josephson junctions naturally present in a cuprate superconductor. We demonstrate that strong nonreciprocity arises not only from broken spatial and time-reversal symmetries, but also from enhanced anharmonicity in the current-phase relation, enabled by the atomically thin barrier of the intrinsic junction. The diode efficiency strongly depends on the number of stacked intrinsic junctions, with the highest efficiency occurring in single-junction devices. Notably, these high-temperature superconducting diodes are readily scalable to large arrays, marking a critical step toward practical implementation in energy-efficient computing architectures.
Superconductivity (cond-mat.supr-con), Applied Physics (physics.app-ph)
Operation Regimes and Design Principles of Delta-E Effect Sensors
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Fatih Ilgaz, Elizaveta Spetzler, Patrick Wiegand, Robert Rieger, Jeffrey McCord, Benjamin Spetzler
Delta-E effect-based magnetoelectric sensors have emerged as promising technology for detecting weak magnetic fields at low frequencies. However, the performance of such sensors remains difficult to predict, as signal and noise characteristics are dictated by interdependent parameters such as magnetic layer geometry, magnetic microstructure, and loss. In this work, we present a systematic experimental study of sub-mm-sized delta-E effect sensors, comprising 24 device configurations that vary in magnetic layer thickness and lateral dimensions. The sensors are statistically analyzed to identify the influence of magnetic layer geometry on performance through a combination of measurements and simulations. Our findings reveal three distinct operation regimes - dominated by electronic noise, magnetic noise, and nonlinearities - whose boundaries shift systematically with magnetic layer thickness. This regime behavior governs the trade-offs between sensitivity and noise, ultimately determining the sensor’s limit of detection. Based on these results, the dependency of the regime boundaries on key device parameters is discussed in detail, providing fundamental insights for tailoring sensor performance. As such, this study establishes a necessary foundation for targeted performance optimization and the scalable design of advanced delta-E effect sensor systems.
Materials Science (cond-mat.mtrl-sci)
Revealing the Staging Structural Evolution and Li (De)Intercalation Kinetics in Graphite Anodes via Machine Learning Potential
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Liqi Wang, Xuhe Gong, Zicun Li, Ruijuan Xiao, Hong Li
Revealing the dynamic structural evolution and lithium transport properties during the charge/discharge processes is crucial for optimizing graphite anodes in lithium-ion batteries, enabling high stability and fast-charging performance. However, the dynamic coupling mechanisms among carbon layer kinetics, lithium (de)intercalation/diffusion, and defects regulation remain insufficiently understood. In this study, we developed a universal automated workflow based on machine learning potentials to simulate the dynamic lithium (de)intercalation process. With this approach, the staging structural evolution of lithium-graphite intercalation compounds and their lithium transport behavior were resolved through molecular dynamics simulations. By introducing stacking faults into the graphite structure, we successfully simulated stage transitions driven by carbon layer sliding and reorganization, accompanied by stress release and structural stabilization. The dynamics of carbon layers regulate the lithium (de)intercalation positional selectivity, producing intermediate states with varying lithium concentrations and distributions during cycling. This facilitates the formation and transformation of stage structures while mitigating residual stress accumulation. A fundamental kinetic asymmetry arises between lithium intercalation and deintercalation, driven by the continuous and heterogeneous lithium transport and carbon layer sliding during charge/discharge processes. The carbon defects regulate lithium transport, in which the atomic-scale defects confine intralayer lithium transport and carbon sliding while enabling interlayer transport via dynamic lithium trapping/release mechanisms. Accordingly, for the future design, it is critical to construct structural units with controllable carbon layer sliding/reorganization, and tunable defects to enhance lithium-ion transport.
Materials Science (cond-mat.mtrl-sci)
$μ_\mathrm{2T}(n)$: A Method for Extracting the Density Dependent Mobility in Two-Terminal Nanodevices
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
Christian E. N. Petersen, Damon J. Carrad, Thierry Désiré, Daria Beznasyuk, Jung-Hyun Kang, Dāgs Olšteins, Gunjan Nagda, Dennis V. Christensen, Thomas Sand Jespersen
Measuring carrier mobility as a function of the carrier density in semiconductors using Hall effect is the gold standard for quantifying scattering mechanisms. However, for nanostructures, the Hall effect is not applicable, and the density dependence of mobility is generally inaccessible, rendering Hall effect measurements impractical. Here, we present $ \mu_\mathrm{2T}(n)$ , a new procedure allowing us to extract the density dependent mobility in two-terminal measured nano scale field effect transistors at zero magnetic field from conventional conductance vs gate voltage measurements. We validate $ \mu_\mathrm{2T}$ against standard Hall measurements and then apply the procedure to 256 individual two-terminal InAs nanowire FETs, extracting information about the scattering mechanisms. To illustrate its broad utility, we reanalyze published data in which mobility had been treated as density independent. Our method represents a new powerful tool for optimization and development of nanomaterials crucial for a wide range of new technologies.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Thermodynamic uncertainty relation for feedback cooling
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
Kousuke Kumasaki, Kaito Tojo, Takahiro Sagawa, Ken Funo
Feedback cooling enables a system to achieve low temperatures through measurement-based control. Determining the thermodynamic cost required to achieve the ideal cooling efficiency within a finite time remains an important problem. In this work, we establish a thermodynamic uncertainty relation (TUR) for feedback cooling in classical underdamped Langevin systems, thereby deriving a trade-off between the cooling efficiency and the entropy reduction rate. The obtained TUR implies that simultaneous achievement of the ideal cooling efficiency and finite entropy reduction rate is asymptotically possible by letting the fluctuation of the reversible local mean velocity diverge. This is shown to be feasible by using a feedback control based on the Kalman filter. Our results clarify the thermodynamic costs of achieving the fundamental cooling limit of feedback control from the perspective of the TUR.
Statistical Mechanics (cond-mat.stat-mech)
11 pages, 4 figures
Finite Length Effects and Coulomb Interaction in Ge Quantum Well-Based Josephson Junctions Probed with Microwave Spectroscopy
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
S. C. ten Kate, D. C. Ohnmacht, M. Coraiola, T. Antonelli, S. Paredes, F. J. Schupp, M. Hinderling, S. W. Bedell, W. Belzig, J. C. Cuevas, A. E. Svetogorov, F. Nichele, D. Sabonis
Proximitized Ge quantum wells have emerged as a novel platform for studying Andreev bound states (ABSs), due to their expected strong spin-orbit interaction and high mobility. Here, we used microwave spectroscopy techniques to investigate ABSs in Josephson junctions (JJs) realized in proximitized Ge quantum wells. Spectroscopic signatures observed in a 350 nm junction indicated the presence of multiple ABSs, and were reproduced with a model including finite-length effects. The ABS spectra measured for a $ 1.2~\mu$ m junction were explained by a model including three ABSs in two conduction channels and finite Coulomb interaction. Our work highlights the importance of interactions in JJs and serves as a basis for understanding and manipulating ABSs in Ge-based hybrid devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
Enhancing Plasmonic Superconductivity in Layered Materials via Dynamical Coulomb Engineering
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-11 20:00 EDT
Yann in ‘t Veld, Mikhail I. Katsnelson, Andrew J. Millis, Malte Rösner
Conventional Coulomb engineering, through controlled manipulation of the environment, offers an effective route to tune the correlation properties of atomically thin van der Waals materials via static screening. Here we present tunable dynamical screening as a method for precisely tailoring bosonic modes to optimize many-body properties. We show that ``bosonic engineering’’ of plasmon modes can be used to enhance plasmon-induced superconducting critical temperatures of layered superconductors in metallic environments by up to an order of magnitude, due to the formation of interlayer hybridized plasmon modes with enhanced superconducting pairing strength. We determine optimal properties of the screening environment to maximize critical temperatures. We show how bosonic engineering can aid the search for experimental verification of plasmon mediated superconductivity.
Superconductivity (cond-mat.supr-con)
12 pages, 8 figures
Scalable Production of Photochromic Yttrium Oxyhydride Powder via Ball Milling
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Elbruz Murat Baba, Stefano Deledda, Smagul Karazhanov
Yttrium oxyhydride (YHO) represents one of the most promising photochromic materials discovered in recent years, yet its practical deployment has been severely constrained by the limitations of thin film deposition methods. Here we demonstrate the first successful synthesis of photochromic YHO powders through reactive ball milling under hydrogen atmosphere followed by controlled oxidation a fundamentally scalable approach that overcomes the production barriers facing this technology. High-energy planetary ball milling of yttrium metal under 50 bar hydrogen for 20 hours, followed by controlled oxidation in ultra-dry technical air, yielded nanostructured YHO powders with less than 500 nm particle sizes. These powders exhibit robust photochromic response with reflectance modulation at 850 nm under 405 nm excitation, reversible cycling behavior, and the characteristic memory effect previously observed only in thin films. Powder X-ray diffraction confirms the formation of the cubic YHO phase with lattice expansion consistent with oxygen incorporation into the yttrium hydride structure. Critically, we demonstrate that YHO powders can be processed into polymer composites enabling spatially-resolved photochromic patterning a capability essential for practical device applications. While optimization of optical contrast remains an opportunity for future work, this powder synthesis route fundamentally transforms the manufacturing of YHO-based photochromic systems, enabling mass-scale production using established industrial ball milling infrastructure. These findings establish a viable pathway toward commercial deployment of YHO in smart windows, adaptive optics, and rewritable information storage applications.
Materials Science (cond-mat.mtrl-sci)
7 pages, 3 Figures
Bogoliubov analysis of Higgs mode in trapped Fermi superfluids with spatial inhomogeneity
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-11 20:00 EDT
Kensuke Kakimoto, Junichi Takahashi, Yoshiya Yamanaka
The Higgs mode is a key component in the spontaneous breaking of a continuous symmetry along with the Nambu-Goldstone mode, and has been studied extensively for homogeneous systems. We consider it for inhomogeneous systems, using the superfluid of harmonically trapped ultracold Fermi atomic gas. The Fermionic field operators are expanded in a complete set of wave functions corresponding to inhomogeneous situation. Within the Hatree-Fock approximation, we derive integral equations from the Bogoliubov-de Gennes equations, which lead to the frequencies of the collective modes, including the Higgs and Nambu-Goldstone modes. The results show that the frequency of the Higgs mode equals twice the absolute value of the order parameter at the center of trap. This feature is robust against variations in the interaction strength, trap potential, and temperature. These results are consistent with previous theoretical and experimental studies.
Quantum Gases (cond-mat.quant-gas)
11 pages, 10 figures
Correlation between Exciton Dynamics and Spin Structure in van der Waals Antiferromagnet NiPS3
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Kang Wang, Yingchen Peng, Boying Huang, Chun Zhou, Qianlu Sun, Fujie Tang, Zhenglu Li, Weigao Xu, Kezhao Du, Xingzhi Wang, Ye Yang
The emerging magnetic van der Waals (vdW) materials provide a platform for exploring novel physics regarding magnetism in low dimensions and developing ultrathin spintronic applications. Here, we investigate the ultrafast dynamics of excitons in a vdW NiPS3 crystal. The temporal evolution of the transient reflection spectra indicates that the spin-correlated exciton is formed through photocarrier localization, the rate of which is independent of the magnetic degrees of freedom. However, the recombination rate of these excitons is connected with the long-range magnetic order, and this connection probably arise from a spin-flip rooted in the underlying antiferromagnetic background during the recombination. Our findings uncover intertwined coupling between carrier, lattice and spin degrees of freedom in NiPS3, which may pave the path toward ultrafast optical manipulation of spin-related quantum states in vdW antiferromagnets.
Materials Science (cond-mat.mtrl-sci)
Active Particle Doping Suppresses Brittle Failure in Ultrastable Glasses
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-11 20:00 EDT
Rashmi Priya, Jürgen Horbach, Smarajit Karmakar
Ultrastable glasses are known for their exceptional mechanical stability but often fail in a brittle manner, typically marked by the formation of shear bands when subjected to shear deformation. An open question is how shear banding is affected by active particles. Here, we address this issue by investigating ultrastable glasses that are doped with self-propelled particles (SPPs) that perform run-and-tumble motions. In the presence of active particles we find a crossover from heterogeneous to homogeneous yielding. Through extensive computer simulations of a polydisperse model, which is capable of producing ultrastable glasses using swap Monte Carlo Methods, we demonstrate the progressive emergence of multiple shear bands under activity, leading to continuous and delayed yielding. Interestingly, we uncover a compensatory relationship between active forces and global shear rates: a rise in one can offset a decline in the other, arising from the isomorphic-like behavior exhibited by different combinations of active forces and strain rates. We also identify a non-monotonic relationship between yielding and persistence time: while the yield stress increases at shorter persistence times with increasing active forces, it tends to decrease with longer persistence times. This observation highlights a tunable range of activity that can modify the yielding mode. Lastly, we show that the spacing between shear bands diminishes in a power law manner as the magnitude of the active force increases.
Soft Condensed Matter (cond-mat.soft), Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech)
Topological bound states in a lattice of rings with nearest-neighbour interactions
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-11 20:00 EDT
Yunjia Zhai, Ayaka Usui, Anselmo M. Marques, Ricardo G. Dias, Verònica Ahufinger
We study interaction-induced bound states in a system of ultracold bosons loaded into the states with orbital angular momentum in a one-dimensional staggered lattice of rings. We consider the hard-core limit and strong nearest-neighbour interactions such that two particles in next neighbouring sites are bound. Focusing on the manifold of such bound states, we have derived the corresponding effective model for doublons. With orbital angular momentum $ l=1$ , the original physical system is described as a Creutz ladder by using the circulations as a synthetic dimension, and the effective model obtained consists of two Su-Schrieffer-Heeger (SSH) chains and two Bose-Hubbard chains. Therefore, the system can exhibit topologically protected edge states. In a structure that alternates $ l=1$ and $ l=0$ states, the original system can be mapped to a diamond chain. In this case, the effective doublon model corresponds to a Creutz ladder with extra vertical hoppings between legs and can be mapped to two SSH chains if all the couplings in the original system are equal. Tuning spatially the amplitude of the couplings destroys the inversion symmetry of these SSH chains, but enables the appearance of multiple flat bands.
Quantum Gases (cond-mat.quant-gas)
15 pages,11 figures
Surface tension of monoatomic liquids after relaxation: the main energy contributions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
Dmitry M. Naplekov, Vladimir V. Yanovsky
We consider the atomistic origin and the main mechanisms determining the energy of a liquid interface after relaxation. A simple theory is constructed for the monatomic densely packed liquids that allows calculation of the surface tension coefficients based on the interatomic potential parameters, without fitting coefficients. Considered are the potential energies of both <
Statistical Mechanics (cond-mat.stat-mech)
On-the-Fly Machine Learning of Interatomic Potentials for Elastic Property Modeling in Al-Mg-Zr Solid Solutions
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Lukas Volkmer, Leonardo Medrano Sandonas, Philip Grimm, Julia Kristin Hufenbach, Gianaurelio Cuniberti
The development of resilient and lightweight Aluminum alloys is central to advancing structural materials for energy-efficient engineering applications. To address this challenge, in this study, we explore the elastic properties of Al-Mg-Zr solid solutions by integrating advanced machine learning (ML) techniques with quantum-mechanical (QM) atomistic simulations. For this purpose, we develop accurate and transferable machine-learned interatomic potentials (MLIPs) using two complementary approaches: (i) an on-the-fly learning scheme combined with Bayesian linear regression during ab initio molecular dynamics simulations, and (ii) the equivariant neural network architecture MACE. Both MLIPs facilitate the prediction of composition-dependent elastic properties while drastically reducing the computational cost compared to conventional QM methods. Comparison with ultrasonic measurements shows that the deviation between simulation and experiment remains within a few GPa across all Al-Mg-Zr systems investigated. These potentials also enable the systematic exploration of the Al-Mg-Zr solid solution phase space and provide insights into the elastic behavior as a function of alloying element concentration. Hence, our findings demonstrate the reliability and transferability of the parameterized on-the-fly MLIPs, making them valuable for accelerating the design of Al alloys with tailored physicomechanical properties in complex compositional spaces. While the present study focuses on homogeneous phases, it establishes a foundation for future multiscale simulations that include microstructural features such as precipitates and grain boundaries.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
17 pages, 6 figures, 1 table
An explicit formula of the Oslo stationary state
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
Valentin Lallemant, Vincent Rossetto
In most sandpile models under driven-dissipative condition, a critical stationary state is known to emerge. This state displays organization features encoded in the dynamical (e.g. avalanche spectrum) and static (e.g. hyperuniformity) observables. However, the access to the explicit stationary state expression happens only in few cases, and for most sandpile models the question is still open. In this article, we derive such an expression for the Oslo model. To do so, we use different representations of the system configurations and of the dynamical process. Back and forth between these representations allows to tag invariant quantities to each configurations. The stationary probabilities are obtained by summing over all paths leading to a given configuration under the constraint specified by the invariants. This description corresponds exactly to a parametrized path integral formulation in discrete space-time.
Statistical Mechanics (cond-mat.stat-mech)
34 pages 3 Tables 14 Figures
An underdog story: Re-emergence of a polar instability at high pressure in KNbO3
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Mohamad Baker Shoker, Sitaram Ramakrishnan, Boris Croes, Olivier Cregut, Nicolas Beyer, Kokou Dorkenoo, Pierre Rodière, Björn Wehinger, Gaston Garbarino, Mohamed Mezouar, Marine Verseils, Pierre Fertey, Salia Cherifi-Hertel, Pierre Bouvier, Mael Guennou
Ferroelectricity in perovskites is known to be suppressed by a moderate hydrostatic pressure. The notion that a polar instability should reappear in a higher pressure regime is well accepted theoretically but experiments have failed so far to provide a conclusive evidence for it. Here, we investigate a classical but comparatively underlooked ferroelectric perovskite KNbO3. We use single crystal X-ray diffraction, infrared and Raman spectroscopy and second-harmonic generation to explore the phase transition sequence at high pressures up to 63 GPa. We show that the ferroelectric instability manifests itself in the emergence of an incommensurate modulation of the perovskite structure that combines cation displacements and tilts of the oxygen octahedra. Soft modes associated to the tilts and the modulation are clearly observed along with persistent order-disorder signatures. This demonstrates the presence of the high-pressure polar instability in a lead-free perovskite in spite of the centrosymmetric character of all observed high-pressure phases.
Materials Science (cond-mat.mtrl-sci)
7 pages, 4 figures
Gate reflectometry in a minimal Kitaev chain device
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
Yining Zhang, Ivan Kulesh, Sebastiaan L. D. ten Haaf, Nick van Loo, Francesco Zatelli, Tijl Degroote, Christian G. Prosko, Srijit Goswami
Hybrid quantum dot (QD)-superconductor system can be used to realize Majorana zero modes in artificial Kitaev chains. These chains provide a promising platform for the realization of Majorana qubits. Radio-frequency (RF) gate reflectometry is a fast, non-invasive, and sensitive technique that can be used to read out such qubits. In this work, we use gate reflectometry to probe two QDs coupled via a semiconductor-superconductor hybrid segment. We demonstrate that gate sensing can resolve charge stability diagrams and clearly distinguish between elastic cotunneling and crossed-Andreev reflection, the two key processes that allow one to form a Kitaev chain. Furthermore, we show that this information is accessible, even when the system is completely decoupled from the from the normal leads. In this closed regime, we show that the observed quantum capacitance signal is indicative of parity switching between the even and odd ground states. Our measurements in both open and closed regimes confirm that gate reflectometry captures the essential features of interdot coupling and parity dynamics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
15 pages, 4 main figures, 5 supplementary figures
Programing optical properties of single-walled carbon nanotubes with benzoyl peroxide derivatives of tailored chemical characteristics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Andrzej Dzienia, Patrycja Taborowska, Pawel Kubica-Cypek, Dawid Janas
Semiconducting single-walled carbon nanotubes (SWCNTs) have great potential for optoelectronics and photonics, further enhanced by covalent functionalization. However, scalable and controlled surface modification is challenging due to complex methodologies and unstable reagents. Benzoyl peroxide (BPO) has emerged as a simple alternative for introducing luminescent defects into SWCNTs. Yet, the lack of understanding of its radical chemistry limits precise defect engineering using BPOs. This is a major obstacle to the effective application of BPO in chemistry, despite its widespread use as a radical initiator. We present a thorough investigation into the radical chemistry of self-synthesized BPOs for functionalizing polymer-wrapped (6,5) and (7,5) SWCNTs in non-polar solvents, providing critical insights into the decomposition of BPO and its analogs. By varying the electronic and steric properties of typically unavailable BPO derivatives, we demonstrate tunability over the photoluminescence characteristics of SWCNTs, allowing control over defect density and light emission wavelength. This toolbox of BPO derivatives, created with simple radical chemistry and accessible organic precursors, alongside clarified structure-property relationships, facilitates effective implementation of BPO in chemical transformations and meticulous engineering of luminescent defects in SWCNTs for optoelectronic applications. Notably, this research offers insights into why SWCNTs modified with electron-deficient reactants provide the best optical characteristics.
Materials Science (cond-mat.mtrl-sci)
Pages 1-30 (main text), pages 31-51 (supporting information)
Leveraging transfer learning for accurate estimation of ionic migration barriers in solids
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Reshma Devi, Keith T. Butler, Gopalakrishnan Sai Gautam
Ionic mobility determines the rate performance of several applications, such as batteries, fuel cells, and electrochemical sensors and is exponentially dependent on the migration barrier ($ E_m$ ), a difficult to measure/calculate quantity. Previous approaches to identify materials with high ionic mobility have relied on imprecise descriptors given the lack of generalizable models to predict $ E_m$ . Here, we present a graph neural network based architecture that leverages principles of transfer learning to efficiently and accurately predict $ E_m$ across a diverse set of materials. We use a model pre-trained simultaneously on seven distinct bulk properties (labeled MPT), modify the MPT model to classify different migration pathways in a structure, and fine-tune (FT) on a manually-curated literature-derived dataset of 619 $ E_m$ data points calculated with density functional theory. Importantly, our best-performing FT model (labeled MODEL-3) demonstrates substantial improvements in prediction accuracy compared to classical machine learning methods, graph models trained from scratch, and a universal machine learned interatomic potential, with a R$ ^2$ score of 0.703 and a mean absolute error of 0.261 eV on the test set. Notably, MODEL-3 is able to distinguish different migration pathways within a structure and also demonstrates excellent ability to generalize across intercalant compositions and chemistries. As a classifier, MODEL-3 exhibits 80% accuracy and 82.8% precision in identifying materials that are `good’ ionic conductors (i.e., structures with $ E_m <$ 0.65~eV). Thus, our work demonstrates the effective use of FT strategies and architectural modifications necessary for making swift and accurate $ E_m$ predictions, which will be useful for materials discovery in batteries and for predicting other data-scarce material properties.
Materials Science (cond-mat.mtrl-sci)
Collective heat engines via different interactions: Minimal models, thermodynamics and phase transitions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-11 20:00 EDT
Iago N. Mamede, Vitória T. Henkes, Carlos E. Fiore
We investigate the dynamics and thermodynamics of a framework composed of interacting units in which parameters (temperatures and energies) assume distinct values due to the contact with distinct (cold and hot) thermal reservoirs. The influence of different ingredients, such as the contact between thermal baths (simultaneous versus not simultaneous contact), the coupling between them (equal or different couplings) and the topology of interactions (all-to-all and local interactions). Closed expressions for transition lines have obtained, expressed by a linear combination of interaction energies times reciprocal temperatures for the simultaneous thermal contact baths and deviates from it when the contact is not simultaneous. The interplay between performance and dissipation is investigated under different conditions, giving rise to a richness of operation regimes, such as heat-engine and heat pump. The relationship between thermodynamic quantities (power, efficiency and dissipation) allows a careful choice of parameters to ensure the desirable compromise between them. Finally, the influence of different interactions energies (Ising, Potts versus Blume-Emery-Griffiths (BEG) like) are investigated, revealing that Potts interactions in general present superior performances than BEG ones.
Statistical Mechanics (cond-mat.stat-mech)
Multiorbital character of the density wave instability in La$_4$Ni$3$O${10}$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-11 20:00 EDT
A. Suthar, V. Sundaramurthy, M. Bejas, Congcong Le, P. Puphal, P. Sosa-Lizama, A. Schulz, J. Nuss, M. Isobe, P. A. van Aken, Y. E. Suyolcu, M. Minola, A. P. Schnyder, Xianxin Wu, B. Keimer, G. Khaliullin, A. Greco, M. Hepting
Ruddlesden-Popper nickelates exhibit high-temperature superconductivity closely intertwined with charge and spin density wave order. However, fundamental questions persist regarding the interplay between the associated density wave (DW) fluctuations and superconductivity, as well as the orbital character and symmetry underlying the DW instabilities. Here we utilize polarized Raman scattering to investigate the phononic and electronic Raman responses of the trilayer nickelate La$ 4$ Ni$ 3$ O$ {10}$ across its concomitant charge and spin density wave transitions. In addition to distinct phonon anomalies occurring below the transition temperature, we observe a depletion of continuum spectral weight up to 114 meV and a pronounced peak centered at this energy. By combining momentum-selective information from polarized electronic Raman scattering with model calculations involving both Ni-3$ d{x^2 - y^2}$ and Ni-3$ d{z^2}$ orbitals, we identify 114 meV as the energy scale $ 2\Delta\mathrm{DW}$ of the DW gap, characterized by incoherent opening and non-mean-field behavior. Furthermore, the model calculations reveal that the corresponding $ 2\Delta_\mathrm{DW}$ peak exhibits a multiorbital origin, thus shedding light on the nature of the DW instabilities in La$ _4$ Ni$ _3$ O$ _{10}$ .
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
Magnetization-induced reordering of ground states phase diagram in a two-component Bose-Hubbard model
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-11 20:00 EDT
Oskar Stachowiak, Hubert Dunikowski, Emilia Witkowska
We investigate the influence of non-zero magnetization on the ground-state phase diagram of the two-component Bose-Hubbard model. Employing a mean-field theoretical framework, both analytically and numerically, we demonstrate that positions and sizes of specific phases on the diagram are magnetization dependent. In particular, non-zero magnetization introduces different Mott insulator phase boundaries for each of the two components. This effect leads to the emergence of a hybrid phase characterized by the coexistence of superfluid in one of the components and Mott insulator in the another one. Our findings highlight the important role of a conserved quantities, which is magnetization here, in reshaping the phase landscape, significantly influencing the stability and emergence of distinct quantum phases.
Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
9 pages, 4 figures
Comparative study of ensemble-based uncertainty quantification methods for neural network interatomic potentials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Yonatan Kurniawan (1), Mingjian Wen (2), Ellad B. Tadmor (3), Mark K. Transtrum (1) ((1) Department of Physics and Astronomy, Brigham Young University, Provo, Utah, USA, (2) Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, China, (3) Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota, USA)
Machine learning interatomic potentials (MLIPs) enable atomistic simulations with near first-principles accuracy at substantially reduced computational cost, making them powerful tools for large-scale materials modeling. The accuracy of MLIPs is typically validated on a held-out dataset of \emph{ab initio} energies and atomic forces. However, accuracy on these small-scale properties does not guarantee reliability for emergent, system-level behavior – precisely the regime where atomistic simulations are most needed, but for which direct validation is often computationally prohibitive. As a practical heuristic, predictive precision – quantified as inverse uncertainty – is commonly used as a proxy for accuracy, but its reliability remains poorly understood, particularly for system-level predictions. In this work, we systematically assess the relationship between predictive precision and accuracy in both in-distribution (ID) and out-of-distribution (OOD) regimes, focusing on ensemble-based uncertainty quantification methods for neural network potentials, including bootstrap, dropout, random initialization, and snapshot ensembles. We use held-out cross-validation for ID assessment and calculate cold curve energies and phonon dispersion relations for OOD testing. These evaluations are performed across various carbon allotropes as representative test systems. We find that uncertainty estimates can behave counterintuitively in OOD settings, often plateauing or even decreasing as predictive errors grow. These results highlight fundamental limitations of current uncertainty quantification approaches and underscore the need for caution when using predictive precision as a stand-in for accuracy in large-scale, extrapolative applications.
Materials Science (cond-mat.mtrl-sci), Data Analysis, Statistics and Probability (physics.data-an)
A literature-derived dataset of migration barriers for quantifying ionic transport in battery materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-11 20:00 EDT
Reshma Devi, Avaneesh Balasubramanian, Keith T. Butler, Gopalakrishnan Sai Gautam
The rate performance of any electrode or solid electrolyte material used in a battery is critically dependent on the migration barrier ($ E_m$ ) governing the motion of the intercalant ion, which is a difficult-to-estimate quantity both experimentally and computationally. The foundation for constructing and validating accurate machine learning (ML) models that are capable of predicting $ E_m$ , and hence accelerating the discovery of novel electrodes and solid electrolytes, lies in the availability of high-quality dataset(s) containing $ E_m$ . Addressing this critical requirement, we present a comprehensive dataset comprising 619 distinct literature-reported $ E_m$ values calculated using density functional theory based nudged elastic band computations, across 443 compositions and 27 structural groups consisting of various compounds that have been explored as electrodes or solid electrolytes in batteries. Our dataset includes compositions that correspond to fully charged and/or discharged states of electrode materials, with intermediate compositions incorporated in select instances. Crucially, for each compound, our dataset provides structural information, including the initial and final positions of the migrating ion, along with its corresponding $ E_m$ in easy-to-use .xlsx and JSON formats. We envision our dataset to be a highly useful resource for the scientific community, facilitating the development of advanced ML models that can predict $ E_m$ precisely and accelerate materials discovery.
Materials Science (cond-mat.mtrl-sci)
Spontaneous Hole Formation in Cell Monolayers Emerges from Collective Cell Motion
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-11 20:00 EDT
Diogo E. P. Pinto, Jan Rozman, Julia M. Yeomans
Although cell monolayers typically remain confluent, they can spontaneously develop persistent holes as a result of collective cellular motion. Recent studies on MDCK monolayers cultured on soft substrates have revealed that cells can align to create regions of local nematic order, and topological defects that generate localised mechanical stresses which can spontaneously trigger hole formation. To investigate this process, we develop a continuum multi-phase field model that incorporates internal dissipation and active dipolar forces that drive cell shape anisotropy. Our simulations show that reducing substrate friction enhances cell-cell velocity correlations. In this low-friction regime, topological defects give rise to spiral flow patterns that concentrate stress and can trigger hole formation. We further demonstrate that the number and stability of the holes, whether they close or persist, depends on both substrate friction and cellular activity. These findings underscore the critical role of collective cell dynamics in maintaining tissue integrity.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
Observation of momentum dependent charge density wave gap in EuTe4
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
Iftakhar Bin Elius, Nathan Valadez, Gyanendra Dhakal, Volodymyr Buturlim, Sabin Regmi, Dante James, Peter Radanovich, Matthew Yankowitz, Tetiana Romanova, Andrzej Ptok, Krzysztof Gofryk, Dariusz Kaczorowski, Madhab Neupane
The occurrence of charge density wave (CDW) phenomena, particularly in low dimensional rare-earth chalcogenides, has attracted substantial research interest. Among these materials, EuTe4, which features multiple Te layers and a single Eu-Te layer, serves as a promising platform to study the interplay between CDW order and 4f electron configurations, including magnetism. In this study, First principles based density functional theory (DFT) calculations were carried out to investigate the electronic band structure modifications arising from CDW modulation. Angle resolved photoemission spectroscopy (ARPES) revealed the emergence of a CDW gap at the Fermi level, as well as hybridization induced gap features at lower binding energies. The low lying CDW gap reaches its maximum along the Gamma-Y high-symmetry direction and a minimum along GX reflecting the anisotropic nature of the electronic structure. We also performed low temperature heat capacity measurements in applied magnetic fields near the Neel temperature (TN ~ 6.9 K) to construct the magnetic phase diagram of EuTe4. This study provides valuable insight into the directional dependent evolution of the Fermi surface nesting induced CDW ordering, along with other observed gap openings within this system.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
9 pages, 4 figures
Simulating Floquet non-Abelian topological insulator with photonic quantum walks
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-11 20:00 EDT
Quan Lin, Tianyu Li, Haiping Hu, Wei Yi, Peng Xue
Floquet non-Abelian topological phases emerge in periodically driven systems and exhibit properties that are absent in their Abelian or static counterparts. Dubbed the Floquet non-Abelian topological insulators (FNATIs), they are characterized by non-Abelian topological charges and feature multifold bulk-boundary correspondence, making their experimental observation challenging. Here we simulate the FNATI using a higher-dimensional photonic quantum walk and develop dynamic measurement schemes to demonstrate key signatures of the FNATI. Importantly, combining a direct bulk-dynamic detection for the underlying quaternion topological charge, and a spatially-resolved injection spectroscopy for the edge states, we experimentally establish the multifold bulk-boundary correspondence, and, in particular, identify the anomalous non-Abelian phase where edge states appear in all band gaps, despite the presence of a trivial topological charge. Our experiment marks the first experimental characterization of the FNATI, providing general insight into the non-Abelian topological phases.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas), Optics (physics.optics), Quantum Physics (quant-ph)
9 pages, 4 figures
Fate of an impurity strongly interacting with a thermal Bose gas
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-11 20:00 EDT
Jiří Etrych, Sebastian J. Morris, Simon M. Fischer, Gevorg Martirosyan, Christopher J. Ho, Moritz Drescher, Manfred Salmhofer, Zoran Hadzibabic, Tilman Enss, Christoph Eigen
We spectroscopically study mobile impurities immersed in a homogeneous bosonic bath (a box-trapped Bose gas), varying the bath temperature and the strength of impurity-bath interactions. We compare our results to those for a quasipure Bose-Einstein condensate (BEC), and find that for strong impurity-bath interactions, the spectra narrow with increasing temperature, while the impurity energy shift is suppressed. Near the critical temperature for condensation, many-body effects still play an important role, and only for a nondegenerate bath, the system approaches the classical Boltzmann-gas behavior. The key spectral features are reproduced within the theory of an ideal Bose polaron.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph), Quantum Physics (quant-ph)
Main Text (5 pages, 3 figures), Supplemental Material (2 pages, 3 figures)