CMP Journal 2026-06-08
Statistics
Nature Materials: 2
arXiv: 66
Nature Materials
Stretchable high-fill-factor silicon-liquid metal platform for multilevel visual acquisition and depth sensing
Original Paper | Electrical and electronic engineering | 2026-06-07 20:00 EDT
Chansul Park, Do Hyeon Kim, Woosang You, Jinyoung Jang, Hyeonseung Choi, Sehui Chang, Donggook Joo, Ji Su Kim, Jisang Ha, Dongyun Lee, Ji Hoon Kim, Mincheol Lee, Young Min Song, Dae-Hyeong Kim
High-density stretchable pixelated electronics that conform to complex, non-developable surfaces are key enablers of next-generation robotic vision systems, skin-mountable sensors and wearable electronics. Existing strategies for stretchable pixelated device arrays–such as buckling mechanics, pop-up structures, serpentine interconnects and kirigami designs–have offered partial solutions. However, a strategy that simultaneously achieves high device performance, stretchability, fill factor and integration density has remained elusive. Here we present a next-generation platform for stretchable pixelated electronics that integrates high-performance single-crystalline silicon pixels with finely patterned liquid metal interconnects on ultrathin elastomeric substrates. We developed a monolithic microfabrication strategy that enables customizable, densely packed and mechanically compliant pixelated device arrays. Using this platform, we demonstrate shape-reconfigurable imaging devices that achieve superb fill factors of up to 81% and a biaxial stretchability of 100%. We also present a human-eye-inspired robotic vision system with tunable focus and a skin-mountable lens-free imaging system. The complementary operation of retinal and epidermal imaging systems enables multiscale visual acquisition and depth sensing.
Electrical and electronic engineering, Electronic devices, Mechanical engineering, Polymers, Sensors and biosensors
Ultralow-voltage electrochemical organic light-emitting transistors with pinned and wide lateral recombination
Original Paper | Electronic devices | 2026-06-07 20:00 EDT
Kwan-Nyeong Kim, Huanyu Zhou, Dong-Yoon Kim, Min-Jun Sung, Woo Jin Jeong, Dae-Gyo Seo, Jinwoo Park, Seungbeom Lee, Yilei Wu, Yeongjun Lee, Kyun Kyu Kim, Jaeho Park, Yanxiang Cheng, Hea-Lim Park, Zhenan Bao, Tae-Woo Lee
Light emission from organic transistors holds strong potential for user-interactive functionality across applications ranging from wearable and biointegrated systems to neuromorphic electronics. However, conventional single-active-layer organic transistors suffer from inefficient charge carrier injection, resulting in high drain voltages (>80 V in field-effect devices and >3.5 V in electrochemical devices with p-i-n junctions) and narrow, spatially dynamic recombination zones (<75 μm). Here we report a single-active-layer electrochemical organic light-emitting transistor with drain-side electric double layer formation, achieving ultralow-voltage operation (<3.5 V) together with a wide, spatially pinned recombination zone. An ion transport enhancer in the light-emitting polymer channel induces an electric double layer at the drain electrode, overcoming limited electron injection without n-type doping. This mechanism enables flexible, large-area devices with a recombination zone width of 267 μm and a maximum luminance of 826 cd m-2 at 3.5 V, and operation with two 1.5-V batteries. This work advances single-active-layer OLETs and paves the way for organic electronic systems with intuitive, user-friendly visualization functions.
Electronic devices, Materials science
arXiv
Element-Specific Solute Trapping and Grain Structure Evolution during Laser Powder Bed Fusion of Multicomponent Alloys
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Xinxin Yao, James Hanagan, Md Shafiqur Rahman Jame, Mallikharjun Marrey, Mohsen Taheri Andani, Raymundo Arróyave, Veera Sundararaghavan, Lei Chen
Under the rapid solidification conditions of laser powder bed fusion (LPBF), solute trapping manifests in an element-specific manner, altering nonequilibrium partitioning, constitutional undercooling, and grain selection behavior in multicomponent alloys. Here, we elucidate the mechanisms by which element-specific solute trapping governs nucleation behavior and grain structure evolution during LPBF demonstrated on a SS316L. This requires quantitative description of nonequilibrium multicomponent thermodynamics and grain evolution across broad LPBF solidification conditions, which is achieved through a CALPHAD-informed Gaussian Process Regression (GPR)-assisted Phase-Field (PF) approach. The predicted transitions in grain morphology and grain size are validated against EBSD measurements under multiple LPBF processing conditions. Results demonstrate that increasing solidification rate drives a composition-dependent transition from solute diffusion-controlled nucleation to solute trapping-controlled grain growth, where nonequilibrium solute redistribution intensified by solute trapping suppresses equiaxed grain formation despite high cooling rates. Quantitative decomposition of multicomponent undercooling further reveals distinct element-specific sensitivities to solute trapping, where C, Cr, and Mo remain dominant contributors to the overall undercooling, while the undercooling contribution of low-partitioning elements such as S and P are strongly suppressed relative to their equilibrium values under rapid solidification conditions. These results reveal how element-specific solute trapping governs grain selection in multicomponent alloys, providing a mechanistic basis for alloy design under nonequilibrium solidification conditions.
Materials Science (cond-mat.mtrl-sci)
Self-organized Floquet band geometry in cavity-driven quantum materials
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-08 20:00 EDT
Christopher Yang, Gil Refael, Mark S. Rudner, Iliya Esin
Floquet engineering has emerged as a powerful route to dynamically control band structure and topology in quantum materials, but most implementations rely on externally imposed laser fields that are power intensive, difficult to integrate into devices, and weakly coupled to the electronic system. We propose and analyze an alternative paradigm in which a self-generated cavity field Floquet-dresses the electronic bands and produces a geometric Hall response in an electrically driven cavity material system. We consider a semiconductor layer embedded in a cavity and coupled to external leads and a bath of acoustic phonons, where dc pumping leads to the buildup of a coherent intracavity field through light-matter coupling. We determine the resulting nonequilibrium steady state self-consistently and show that, above threshold, the coupled system settles into a stable time-periodic limit cycle with a field amplitude set by the cavity quality factor and dissipation. This emergent periodic field Floquet-dresses the electronic bands and modifies the anomalous Hall response of a material with broken time-reversal symmetry. We demonstrate that the resulting Hall conductivity can be directly probed via in-plane dc transport measurements. Our work establishes a route to self organized Floquet band reconstruction and geometric transport without external laser illumination, highlighting cavity driven steady states as a platform for electrically controlled nonequilibrium phases.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
19 pages, 7 figures + supplemental information
Bootstrap bounds for Quantum Spin Systems using String Operators
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Nisarg Chadha, Michael G. Scheer, Eslam Khalaf
Bootstrap is a numerical many-body method that provides rigorous bounds on ground-state observables by imposing a set of necessary constraints on the expectation values of operators. The quality of the resulting bounds is sensitive to the choice of operators entering the constraints. In particular, bounds on ground-state correlations are often loose in spontaneous symmetry-breaking (SSB) phases, since local operator sets cannot exclude domain-wall excitations. In this work, we introduce non-local, string-like operators into the bootstrap and show that the program can be formulated directly in thermodynamic limit. We then apply our construction to several 1D spin models. First, we obtain a significant tightening of the bounds in the SSB phase of the 1D transverse-field Ising model. Using the 1D axial next-nearest-neighbor Ising model, we further show that this tightening allows for a quantitative estimate of the locations of phase boundaries. Finally, we generalize the string operators to the 1D $ \mathbb{Z}_3$ chiral clock model and track the behavior of the bounds across the phase diagram. Our results broaden the class of constraints available to the bootstrap and open a route toward bootstrapping more general symmetry-broken and topological phases, where the relevant constraints may involve non-local or extended operators.
Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 4 figures
Tensor network study of deconfined quantum criticality in a one-dimensional spin-phonon model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Anton Romen, Josef Willsher, David Hofmeier, Johannes Knolle, Michael Knap
Deconfined quantum critical points (DQCPs) describe continuous transitions between ordered phases beyond the Landau paradigm. A simple example is the Néel antiferromagnet (AFM) to valence bond solid (VBS) transition in a 1D antiferromagnetic $ J_1-J_2$ model. In analogy to the spin-Peierls instability of critical spin chains, DQCPs are predicted to be unstable towards lattice distortions below a critical phonon frequency. In this work, we use tensor network simulations to investigate this instability in the antiferromagnetic $ J_1-J_2$ model coupled to lattice vibrations. We confirm the stability of DQCP for large phonon frequencies and demonstrate that the transition turns strongly first-order below a critical frequency. The instability is caused by a reduction of the Luttinger parameter due to spin-phonon interactions and we identify the effective theory of the behavior as the double sine-Gordon model. The same effective theory is known to describe the classical Ashkin-Teller model, which enables us to show that the critical endpoint is in the four-state Potts universality class. Furthermore, we provide quantitative numerical scaling results for the phonon spectral function, offering an experimental signature to probe DQCP-phonon coupling in low-dimensional materials.
Strongly Correlated Electrons (cond-mat.str-el)
18 pages, 14 figures
Temperature-Induced Crossover of Coherent Phonon Mechanisms in Chiral 2D Perovskites
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Katherine A Koch, Matthew P Hautzinger, Matthew C Beard, Ajay Ram Srimath Kandada
The coupling between electronic excitations and lattice degrees of freedom fundamentally dictates the optoelectronic functionality of hybrid perovskites. While the potential energy surfaces (PESs) of the electronic excited states are typically considered static, albeit modulated by thermal disorder, the exact nature of their structural evolution with temperature remains elusive. Here, we demonstrate that the excited-state structural reconfiguration in two-dimensional metal-halide perovskites is explicitly temperature-evolving, governed by lattice compliance. We select a chiral perovskite framework with an exceptionally large, temperature-dependent bond angle variance to maximize the structural compliance. Through phase-resolved resonant impulsive stimulated Raman scattering, we measure the coherent phonon dynamics and resolve the real-time structural pathways of exciton-lattice dressing. We observe a temperature-induced crossover from field-driven Impulsive Stimulated Raman Scattering (ISRS) to population-driven Displacive Excitation of Coherent Phonons (DECP). While momentum-driven ISRS pathways dominate at low temperatures, increasing thermal energy softens the lattice and enhances coordinate-driven displacive pathways, allowing excitons to sample steeper, highly anharmonic regions of the excited-state PES. Our results show that temperature can actively modulate the excited-state structural coordinates of flexible 2D frameworks, offering a practical strategy to tune exciton-lattice interactions in chiral optoelectronics.
Materials Science (cond-mat.mtrl-sci)
Matching Terahertz and Hall Mobilities as a Hallmark of Intrinsic Charge Transport in Metal-Halide Perovskites
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Dmitry R. Maslennikov, Ben P. Carwithen, Vladimir V. Bruevich, Yichao Cai, Davide Nodari, Navendu Mondal, Xijia Zheng, Beier Hu, Nicola Gasparini, Jarvist M. Frost, Vitaly Podzorov, Artem A. Bakulin
Charge-carrier transport in soft-lattice materials, including metal-halide perovskites, is often perceived to be highly heterogeneous across different length scales, and influenced by both the intrinsic (dynamic) thermal electronic disorder and extrinsic (static) disorder due to crystal defects, impurities, grain boundaries, and surface states. As a consequence, the reported carrier mobilities obtained by different electrical and optical measurement techniques frequently disagree, raising a critical question: can a truly intrinsic charge transport regime (that is, a regime not dominated by static disorder) extend across macroscopic single crystals of these materials? Here, we demonstrate such a regime in an exemplary metal-halide perovskite system, epitaxial CsPbBr$ _{3}$ single crystals, where the local mobility obtained via optical pump-terahertz probe (OPTP) spectroscopy quantitatively agrees with the macroscopic transport mobility across a broad range of experimental conditions. Using a dedicated device platform that enables concurrent Hall-effect and OPTP measurements on the same single-crystalline sample, we obtain consistent room-temperature mobilities of ~ 30 cm$ ^{2}$ V$ ^{-1}$ s$ ^{-1}$ , among the highest reliably reported for CsPbBr$ _{3}$ . Both techniques reveal band-like temperature dependence of the hole mobility with similar power exponents, confirming that the same intrinsic transport mechanism governs the ultrafast/local and steady-state/macroscopic responses. These results show that defect-free charge transport is achievable in soft-lattice perovskites on millimetre length scales and establish a robust methodology for benchmarking intrinsic mobility in emerging semiconductors.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
Non-Hermitian Crystalline Braid Topology from Hermitian Projection: A Zero-Mode Resonance Mechanism
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-08 20:00 EDT
Stefan Đorđević, Vladimir Juričić
Non-Hermitian topological phases are usually engineered through gain, loss, asymmetric couplings, or explicit environmental channels. Here we show that non-Hermitian crystalline braid topology can instead emerge from projection alone, starting from a fully Hermitian and topologically trivial parent lattice. The mechanism is zero-mode-resonant projection. When the eliminated complement is zero-mode free, projection has a smooth low-frequency limit and reduces to a static Schur complement, yielding conventional SSH-type descendants. When a complement zero mode couples to the retained subsystem, the embedding self-energy develops a pole, the zero-frequency limit becomes singular, and topology is carried by the finite-frequency projected Green’s function-where frequency is a tunable parameter, the drive frequency in a circuit realization, for instance. We demonstrate this mechanism in an exactly solvable model, a trivial nearest-neighbor square lattice with an embedded one-dimensional zig-zag brane. Odd-parity periodic sectors are resonant: a sublattice-imbalance zero mode generates the singular self-energy, and the complex spectrum forms an abelian two-band braid whose transitions occur only at isolated finite frequencies. Although the internal class is $ \text{AI}^†$ featuring only trivial phases, embedding parity induces conjugated pseudo-Hermiticity (CPH), quantizes the complex Berry phase, and identifies it with the braid count. The model is free of the non-Hermitian skin effect, making the invariant a genuine Bloch bulk quantity. In topolectrical realizations, the same finite-frequency braid transitions appear as transmission zeros and admittance features at the predicted drive frequencies.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
49 pages main text, 17 pages SM, 31 figures
Charge density waves and enhanced superconductivity in the electron-hole gas: a plausible, simple, physically intuitive model
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-08 20:00 EDT
A neutral degenerate plasma of equal numbers of electrons and positively charged fermions (holes) – the electron-hole gas – is studied using a simple, physically motivated two-parameter model (density r_s and mass ratio M/m). Two simplifying assumptions are made but not proven: the electron-hole correlation energy is approximately independent of density and does not affect the pressure or bulk modulus, and the electron-hole contribution to the local field factors is zero, allowing use of the known electron-gas local field factors. With these assumptions the phase diagram, instabilities, and effective interactions can be calculated for all mass ratios and densities using simple formulae, reproducible on a laptop. The key new physics is the additional screening provided by the mobile holes. A single function Delta appears in the denominator of all effective interactions and response functions. Near the zeros of Delta at q = 0 (compressibility instability) and at finite q, three phenomena are simultaneously enhanced: charge density waves (for M/m >= 4.97), a large T^2 electrical resistivity from electron-hole scattering, and an attractive electron-electron interaction that is the purely electronic analog of BCS electron-phonon coupling. Crudely estimated superconducting transition temperatures approach room temperature, reaching approximately 275 K at M/m = 9. No claim is made that this model applies to any specific material. The aim is to provoke scrutiny of the assumptions, calculation of the unknown local field factors, and investigation of whether this minimal two-carrier framework maps onto real systems.
Superconductivity (cond-mat.supr-con), Other Condensed Matter (cond-mat.other), Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el)
22 pages, 10 figures
Riemann Rarefaction Waves in a Strongly Interacting Fermi Gas
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-06-08 20:00 EDT
Eric A. Wolf, Martin Zwierlein
We investigate the expansion of a homogeneous, strongly interacting Fermi gas released into vacuum in a ``shock tube’’ geometry. At unitarity, where the gas is scale invariant and nearly inviscid, we find that the resulting rarefaction wave dynamics are self-similar and in excellent agreement with Riemann’s solution of the Euler equation for all temperatures probed. Probing interactions away from unitarity within the BEC-BCS crossover, we observe increasing deviations from the Riemann solution as viscosity increases. However, even on the BCS side, where the sound diffusivity is increased twenty-fold, self-similarity is still approximately preserved. This may reflect how 1D Navier-Stokes rarefaction flows approach Euler self-similar solutions at long times. Our work demonstrates the utility of strongly interacting Fermi gases for the study of nonlinear hydrodynamics in a highly controllable setting.
Quantum Gases (cond-mat.quant-gas), Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el)
4+3 Pages, 4+3 Figures
Field-rigid Ising antiferromagnetism with giant spin-flip fields in Van der Waals UOTe
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Zackary Rehfuss, Shannon Gould, Joanna Blawat, Christopher Broyles, George Xu, Yiqing Hao, Huibo Cao, Thao Dinh, Suyang Xu, Dave Graf, John Singleton, Sheng Ran
Van der Waals antiferromagnets provide a route to thickness-controlled magnetic order, but few combine high-temperature Ising order with conducting, correlated, and topological electronic structure. Here we show that UOTe realizes this combination. Magnetic susceptibility reveals a strongly anisotropic paramagnetic response, while neutron diffraction establishes c-axis antiferromagnetic order below $ T_N \simeq 150$ K with an order-parameter exponent $ \beta = 0.14$ , close to the two-dimensional Ising value. Torque magnetometry further shows that the ordered state remains well described by a uniaxial antiferromagnet below the high-field transition. Pulsed-field magnetization up to 73 T shows that the ordered state survives to very large fields applied along the c axis before entering a broad metamagnetic regime that begins near 50 T, and remains unsaturated at the highest measured field. Angle-dependent proximity detector oscillator measurements show that the metamagnetic instability is set by the field component along the ordered moment direction, providing direct evidence for Ising-like field rigidity. UOTe therefore establishes a field-rigid Ising antiferromagnet with giant spin-flip fields in a compensated Van der Waals metal, where high-temperature c-axis order, quasi-two-dimensional magnetic criticality, Kondo-associated uranium 5f hybridization, metallic transport, and symmetry-enabled topology coexist in a single material.
Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 5 figures; Supplemental Material: 6 pages, 17 figures
Symmetry-Protected Phonon Topology and Low Lattice Thermal Conductivity in Square-Octagonal Chalcogenides
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Nair Surabhi Suresh, Mondal Chiranjith, Alam Aftab, Singh Nirpendra
Unconventional lattice geometries provide an effective platform for realizing symmetry-protected topological phonon states that can strongly influence lattice heat transport. In this work, we explore the relationship between topological phonon band features and thermal transport in square–octagonal (so) chalcogenide monolayers, namely MoS2 and SnS, by combining first-principles calculations with phonon Boltzmann transport theory. Symmetry analysis reveals the presence of nontrivial phonon band topology in the form of symmetry-protected nodal lines. Crossings between nodal lines carrying different symmetry eigenvalues produce fourfold Dirac points that enhance the phonon group velocity (vg), whereas nearly flat nodal lines lead to strong suppression of vg. The coexistence of these features, together with substantial phonon softening and enhanced anharmonic scattering around the topological band crossings, markedly suppresses the lattice thermal conductivity ($ \kappa_l$ ). As a result, room-temperature $ \kappa_l$ values of 4.0 W/mK for so-SnS and 18.7 W/mK for so-MoS2 are obtained, representing reductions by more than a factor of two and eight, respectively, relative to their hexagonal phases. Our results uncover a direct connection between phonon band topology and heat transport in two-dimensional materials, highlighting lattice symmetry and topological band engineering as promising routes for tailoring thermal properties. These findings further suggest opportunities for designing topological phononic and thermoelectric devices with controllable heat flow.
Materials Science (cond-mat.mtrl-sci)
Beyond Snap-Fit: Optimizing the Lifting Capabilities of a Partial Cylindrical Shell
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-08 20:00 EDT
Grace K. Curtis, Ian M. Griffiths, Dominic Vella
The cylindrical snap-fit is a ubiquitous fastening method that is both simple to manufacture and assemble, and yet secure. It consists of a partial cylindrical shell that snaps' onto a cylindrical object. We build on previous work to describe the mechanics of the cylindrical snap-fit as a naturally curved thin elastic shell placed atop a rigid cylinder; we investigate the shell's behaviour when subject to a point force pushing it onto or pulling it off the cylinder. We classify the possible contact regimes according to whether the shell has a nonzero lifting capacity. We term situations with lifting capacity grip-fits’ and show that this includes both the snap-fit and a stick-fit' regime, which allows lifting despite not having the characteristic snap’. Regimes without lifting capacity are also characterized for completeness. We show that the different regimes may be characterized entirely by the shell/cylinder geometry and the coefficient of friction. We then consider different metrics for the lifting performance in the grip-fit regime. Our analysis reveals the trade-offs between assembly force, disassembly force, lifting force, and clamping force, providing design principles for secure lifting, easy detachment, and safe handling of fragile objects.
Soft Condensed Matter (cond-mat.soft)
Persistent currents in signed directed networks
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-08 20:00 EDT
Davide Cipollini, Guido Caldarelli
Network theory can be fruitfully used to describe quantum coherence in physical systems. To that purpose we introduce persistent currents in signed directed networks by interpreting the signed magnetic Laplacian as an effective Hamiltonian and the associated edge phases as a discrete gauge field. In a canonical ensemble, persistent currents arise as thermodynamic responses to variations of gauge-invariant fluxes. We show that these fluxes are naturally defined on the cycle space of the network, and that the resulting currents are constrained to the divergence-free subspace and decompose onto independent cycles. This formulation provides a direct generalization of persistent currents from rings and lattices to arbitrary topologies. Detection of persistent currents provides a signature of the quantum phase coherence supported by the network, and a direct signature of the geometry of its cycle space. Such a mapping, not only allows a practical way to deal with quantum coherence for a variety of situations in the field of quantum technologies, but it also allows a physical interpretation of the importance of the Laplacian operator in graph theory, linking its role to the one of Hamiltonian (i.e. a tight-binding one) in physical systems. To test the power of the method, we construct a signed directed network that reproduces the Hofstadter butterfly spectrum.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Engineering magnetic anisotropy and ferromagnetism in topological Kagome metal GdV6Sn6 via Nd substitution
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Santosh Karki Chhetri, M.M. Sharma, Jian Wang, Dinesh Upreti, Gokul Acharya, Md Rafique Un Nabi, Jin Hu
Kagome metals with the formula RM6X6 (R = rare-earth, M = 3d transition metal, and X = Sn/Ge) provide a rich platform for exploring magnetic and electronic phenomena, with tunable properties enabled by the combination of rare-earth elements and transition metals. In this study, we report the structural, electrical and magnetic properties of Kagome metal (NdxGd1-x)V6Sn6. We demonstrate that substituting lighter Nd atoms at the Gd site tunes the complex magnetic ground state of GdV6Sn6 into a ferromagnetic-like one. Moreover, the isotropic magnetization of GdV6Sn6 becomes anisotropic, with the c-axis emerging as the easy axis. Transport measurements reveal a strong coupling between magnetism and electronic properties, with negative magnetoresistance observed at low magnetic fields in all compositions. In addition, a fourfold anisotropy component tends to emerge in end compounds at higher magnetic fields. These findings highlight the role of rare-earth substitution in tuning magnetic anisotropy and magneto-transport behaviour in RM6X6 compounds, featuring a non-magnetic Kagome layer, with potential implications for spintronic and topological applications.
Materials Science (cond-mat.mtrl-sci)
25 pages, 6 figures
Physical Review B 113,224417(2026)
Reactivity-Informed Machine Learning for Performance Prediction and Design Space Exploration of Alkali-Activated Slag
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Qiyao He, Zhanzhao Li, Kai Gong
Establishing quantitative relationships among mix design, raw material properties, curing conditions, and performance remains a long-standing challenge in cementitious materials, particularly for alkali-activated materials with variable precursor and activator chemistry. Here, we curated the largest literature-derived alkali-activated slag (AAS) dataset to date, comprising over 3100 compressive strength records, 155 chemically distinct ground granulated blast-furnace slags (GGBSs), and 24 attributes incorporating precursor chemistry, fineness, and reactivity. Multiple machine learning (ML) algorithms were benchmarked across progressively enriched feature scenarios, demonstrating that integrating GGBS compositions, fineness, curing conditions, and specimen geometry improves predictive performance. The average metal oxide dissociation energy (AMODE), a physically interpretable representation of precursor reactivity, provides a compact alternative descriptor to explicit oxide compositions while enabling comparable predictive performance. Model interpretation revealed physically consistent trends from heterogeneous data, including non-monotonic effects of Na2O dosage and silicate modulus, reduced predicted strength at higher water content and larger specimen size, and coupled oxide-level effects more coherently represented by AMODE than by individual oxide contents. Statistically constrained design space exploration reveals reactivity-dependent trade-offs among strength, embodied CO2 emissions, and cost. The design maps identify high-strength regions with substantially lower CO2 emissions than OPC-based references at similar cost. Overall, this work demonstrates how reactivity-informed ML can extract physically meaningful trends from heterogeneous AAS data and guide source-dependent binder design. The curated dataset is publicly accessible to support advances in cement and concrete research.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
68 pages, 14 figures, 2 tables
Atomic-scale phase-field modeling for 2D ferroelectrics including non-Gaussian fluctuations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Atomic-scale phase-field modeling extends the phase-field framework down to the level of individual atoms by treating the probability density of atomic vibrations as a field variable and constructing a corresponding free-energy functional from this atomic field together with interatomic potentials. In this way, the framework has the potential to visualize local thermodynamic states with atomic-level resolution, just as conventional phase-field modeling has served as a computational microscope for free energy, stress, and related quantities at mesoscopic scales. However, existing formulations mainly assume Gaussian probability distributions for atomic vibrations, which limits their applicability to more complex and heterogeneous systems such as surfaces. In this work, we generalize the atomic-scale phase-field methodology by extending the free-energy functional to include non-Gaussian fluctuations. We apply this approach to monolayer SnTe in the NVT ensemble and show that the predicted equilibrium polarization is in better agreement with molecular dynamics simulations and that the ferroelectric-to-paraelectric phase transition is successfully reproduced. Furthermore, by decomposing the entropy on a per-atom basis, we visualize atomically resolved maps of local entropy and find that Sn atoms contribute more strongly to the entropy than Te atoms at high temperature, which is a driving factor of the ferroelectric-to-paraelectric phase transition. These results broaden the applicability of phase-field approaches to a wider range of atomic systems and suggest a route toward an atom-resolved theory of phase transitions based on high-resolution thermodynamics.
Materials Science (cond-mat.mtrl-sci)
Descriptor Covariance and Correlation Hierarchy in Moiré Exciton Photoluminescence
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-08 20:00 EDT
We develop a minimal theory for the spatial organization of photoluminescence spectra in moiré transition-metal dichalcogenide heterobilayers. Motivated by hyperspectral mapping of MoSe$ 2$ /WSe$ 2$ , which reveals micron-scale correlations among nine peak-decomposition-free spectral descriptors, we propose a descriptor-based disorder-filter picture in which different descriptors probe different components of a multi-scale disorder landscape, producing a hierarchy of spatial correlation lengths. The central result is the correlation hierarchy $ \xi(E{\rm cent}) \ge \xi(E{\rm dom})$ , derived from the decomposition of the dominant-peak energy into a smooth background contribution and a short-range trap-switching fluctuation term. The same framework explains the principal inter-descriptor Spearman correlations, including the near-perfect anti-correlation $ \rho_{\rm S}(\Delta E_{\rm cd}, R_{\rm HL}) \approx -0.978$ as a robust spectral-shape relation for spectra with a dominant unimodal envelope. The framework provides a peak-decomposition-free route to infer effective disorder parameters from hyperspectral data through the descriptor covariance structure, without microscopic line assignment.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
25 pages, 9 figures
Magnetic Field Walls in Flat-band Superconductors
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-08 20:00 EDT
Guodong Jiang, Aaron Dunbrack, Tero Heikkilä, Päivi Törmä
Superconductors of different types have distinct magnetic properties; for example, they can form Abrikosov vortices or alternating normal-superconducting domains. We predict that, in flat bands, a superconducting phase exhibiting walls of magnetic flux is stable in an applied magnetic field. This phase relies on the lack of a single particle energy penalty for forming condensates of any momentum in flat bands and, consequently, their superconducting free energy being a negative and periodic function of the vector potential at low temperatures. Using a minimal lattice-periodic model of free energy, we study two types of soliton modes of the wall phase: the kink and breather solitons. They determine the lower critical field and the high-field behavior of the wall phase, respectively. The competition between the walls and vortices in flat bands is also discussed. Our results suggest that flat bands help sustain superconductivity in the presence of large magnetic fields.
Superconductivity (cond-mat.supr-con)
19 pages, 14 figures
Complex Temperature-dependent Thermal Conductivity in a Sawtooth Chain Magnet Fe$\mathrm{2}$SiSe$\mathrm{4}$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Kunya Yang, Feihao Pan, Liran Wang, Chenglin Shang, Ying Zhu, Xiancai Hu, Sanjiang He, Xinrun Mi, Long Zhang, Aifeng Wang, Yisheng Chai, Frederic Hardy, Christoph Meingast, Peng Cheng, Mingquan He
Geometrically frustrated magnets provide an ideal platform for exploring the interplay between lattice geometry and spin degrees of freedom. Here, we investigate the interactions between lattice and spin via thermal-transport measurements on the triangular sawtooth-lattice olivine magnet Fe$ _\mathrm{2}$ SiSe$ _\mathrm{4}$ , which exhibits successive magnetic transitions at $ T_1 = 110$ K (antiferromagnetic) and $ T_2 = 50$ K (ferrimagnetic). Although phonons dominate the thermal conductivity, its temperature dependence displays a pronounced double-peak structure arising from spin-phonon coupling. In the intermediate temperature range between $ T_1$ and $ T_2$ , resonant scattering of phonons by magnetic excitations around 5 meV produces a broad maximum around 60 K. Below $ T_2$ , the resonant spin-phonon scattering is strongly suppressed, leading to a rapid increase in thermal conductivity upon cooling and a pronounced low-temperature peak near 11 K, characteristic of heat transport governed by conventional phonon scattering mechanisms. Notably, this low-temperature peak is enhanced by a factor of $ \sim 5$ compared to the broad maximum at higher temperatures. These results demonstrate the strong sensitivity of thermal transport to spin-lattice interactions and highlight spin-phonon scattering as an effective mechanism for tailoring thermal conductivity in geometrically frustrated magnets.
Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 3 figures
Phys. Rev. B 113, 174442(2026)
Impact of capacity volatility and input substitutability on supply chain resilience
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Jaeseok Hur, Juha Jang, Meesoon Ha, Hawoong Jeong
Supply chains are intrinsically vulnerable to stochastic shocks due to their sequential production dependencies. Building on the Feld-Barthelemy framework, we investigate how capacity volatility and input substitutability determine critical demands in stochastic supply chains. By modeling production capacity with a truncated normal distribution, we show that in long supply chains, reducing capacity volatility is often more effective than increasing average capacity, emphasizing the need for firm-level synchronization. Furthermore, introducing a modified Leontief-type production function reveals that input substitutability effectively disperses stochastic shocks. Supplier diversification inherently raises critical demands, even under fixed maximum capacities, by introducing the effect of network topology that independently enhances the resilience of physical stock. Our findings demonstrate that mitigating capacity volatility and structurally diversifying supply routes are just as crucial to supply chain resilience as traditional inventory expansion.
Statistical Mechanics (cond-mat.stat-mech)
8 pages, 4 figures in the main text, and 3 figures in the appendices
A Machine-Learning Based Approach to the Evaluation of the Critical Scaling Behavior of Anisotropic Spin Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Alina A. Chubarova, Ivan A. Mamonov, Marina V. Mamonova, Mikhail I. Bogachev, Pavel V. Prudnikov
Computational models adequately representing phase transitions and evaluating the critical system parameters are essential for the understanding of the properties of a wide range of materials. Here we propose a machine learning (ML)-based approach to the identification of the critical point in anisotropic spin systems. Our approach implies training of a convolutional neural network (CNN) model from the correlation matrices obtained by Monte Carlo simulations. Next, the pretrained model is employed as a fast estimator of the critical temperature, which can be extracted in several complementary ways from the CNN model inference, this way improving the robustness of the analysis. The ML-based estimates obtained in this study are in very good agreement with the reference Monte Carlo simulation results, while computational costs are about 10x lower compared to the classical thermodynamic approach.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn)
Layer-Polarization-Driven Metal-Insulator Transition in multi-band Graphene Moire’ Superlattices
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-08 20:00 EDT
Harsimran Kaur Mann, Simrandeep Kaur, Harsimran Singh, Yashashwani Garg, Amogh Waghmare, Mohit Kumar Jat, Kenji Watanabe, Takashi Taniguchi, Manish Jain, Aveek Bid
Graphene/hBN moiré superlattices provide a highly tunable platform for exploring emergent quantum phases in low-dimensional systems. Here, we investigate the moiré superlattice formed between hBN and ABA-stacked trilayer graphene (TLG), an inherently multi-band system. We demonstrate that the moiré potential is not merely a perturbation but a tool to hybridize the distinct massless and massive electronic sectors of TLG. By applying a perpendicular displacement field to tune layer polarization, we drive a fundamental reconstruction of the electronic band structure. Specifically, increasing the displacement field evolves the system from a multi-band regime to an effectively single-band regime at low energies, accompanied by a metal–insulator transition at the hole-doped secondary Dirac point. This transition originates from a redistribution of carriers across graphene layers that selectively enhances their coupling to the extrinsic moiré potential. Quantum capacitance measurements provide direct evidence for the suppression of the density of states at the hole-side secondary Dirac point, consistent with gap opening and the emergence of a displacement-field-tuned band gap. Theoretical calculations reproduce these observations and identify layer-selective coupling to the moiré potential as the underlying mechanism. These results demonstrate electrical control of an emergent insulating phase in a low-dimensional moiré system, and highlight that layer polarization and layer-selective coupling in multi-band moiré heterostructures provide a powerful route for engineering topological and correlated phases through band structure reconstruction and electron interactions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Spin SWAP operation in double quantum dots at the LaAlO3/SrTiO3 interface
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-08 20:00 EDT
A. Sierant, J. Czarnecki, B. Szafran, P. Wójcik
Progress in the fabrication of nanoscale transition-metal-oxide heterostructures makes these platforms promising candidates for the realization of spin qubits, mainly due to the $ d$ -character of their electronic structures, which could potentially result in a reduction of hyperfine interactions and spin decoherence. Here, we present a systematic study of spin control within the SWAP operation in double quantum dots embedded in a two-dimensional electron gas at the LaAlO$ 3$ /SrTiO$ 3$ interface. Our analysis starts with a study of single-electron spin dynamics, focusing on the influence of spin-orbit and interorbital coupling on the spin evolution. In this case, our findings are supported by semiclassical calculations based on the Bloch equations, which show good agreement with full quantum mechanical simulations. We then simulate the SWAP operation by analyzing the crossover between two regimes: (i) large quantum dots, where the electronic structure is dominated by the $ d{xy}$ orbitals and the spin dynamics is affected primarily by Rashba-type spin-orbit interaction; and (ii) small quantum dots, where higher-energy orbitals $ d{xz/yz}$ contribute to the electronic structure, leading to a significant reduction in the SWAP fidelity. In the first regime, particularly relevant from the application point of view, we analyze in detail the anisotropy of the SWAP operation induced by the spin-orbit coupling.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 14 figures
Characterization of Nonlinear Dynamics in Semiconductors in Frequency Domain using Modulated Photoexcitation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Attia Awan, Rong Tang, Zhou Kang, Khadga Jung Karki
Carrier dynamics in semiconductors is inherently complex owing to the coexistence of different excited species, such as free carriers and excitons, and their interactions among themselves and with traps and phonons. It is usual to use time-resolved responses to identify the processes that contribute to the dynamics. However, the responses often are non-exponential, leading to ambiguity in the interpretation. Here, we propose a frequency domain method to characterize nonlinear dynamics in semiconductors using CdSe as the test system. We show that by analyzing the frequency components in the total photoluminescence induced by a pair of phase-modulated beams, the parameters, such as rates of different types of recombination of free carriers and excitons, can be evaluated. The method can be used as a simple diagnostic tool to characterize ultrafast processes that are relevant to the functionality of semiconductor devices.
Materials Science (cond-mat.mtrl-sci)
Electric-field induced trends of exchange interactions in transition-metal trilayers
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Moinak Ghosh, Stefan Heinze, Souvik Paul
Using density functional theory, we have performed a systematic study of the Heisenberg pairwise exchange interaction and the beyond Heisenberg multi-spin higher-order exchange interactions in unsupported transition-metal trilayers in the presence of external electric fields. The systems consist of a hexagonal atomic Fe layer sandwiched between 4$ d$ (Ru, Rh, and Pd) and 5$ d$ (Ir) transition-metal layers. Both fcc and hcp stacking of the 4$ d$ overlayer has been taken into account. To scan a large part of the magnetic phase space, we have calculated the energy dispersion of spin spirals without and with applied electric fields up to $ \pm 1.0$ V/Å. We find that the energy dispersion remains qualitatively the same upon applying the electric fields and the magnetic ground state remains unchanged. The exchange constants obtained by fitting the energy dispersions exhibit a linear dependence on the electric field up to values of about $ \pm 0.6$ V/Å. The sign of the calculated pairwise and higher-order exchange constants remain unchanged with electric-field, however, their field induced variation is sensitive to the 4$ d$ overlayer. The changes are on the order of a few percent for the nearest-neighbor exchange constant and up to a few ten percent for beyond nearest-neighbor constants. The higher-order exchange constants are calculated based on the total energies of multi-$ Q$ states, such as the $ uudd$ and the 3$ Q$ state. Similar to the pairwise exchange constants, we find a nearly linear field dependence of the higher order constants at small electric fields and variations of up to ten percent. We study the spin-dependent screening of the electric field for the three trilayers and relate the modifications of the pairwise and higher-order exchange interactions to the electric field induced changes of the spin-dependent Fe local density of states and its variation at the Fermi level.
Materials Science (cond-mat.mtrl-sci)
Fate of the Ising universality class under nonreciprocal interactions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
M. Akritidis, A. Garcés, A. Vasilopoulos, M. Carosi, D. Levis, N.G. Fytas
We study the critical behavior of a two-dimensional Ising model with nonreciprocal vision-cone interactions, which explicitly violate reciprocity and detailed balance. Extensive Monte Carlo simulations and dynamic renormalization-group analysis show that the asymptotic critical exponents remain fully consistent with the equilibrium Ising universality class over a broad range of nonreciprocal coupling strengths $ \lambda$ . In contrast, dimensionless quantities such as the Binder cumulant and the correlation-length ratio display pronounced anisotropic nonequilibrium corrections and systematically deviate from their equilibrium Ising values. The renormalization-group flow further demonstrates that the nonreciprocal perturbation is irrelevant at the Wilson-Fisher fixed point while generating a finite shift of the critical temperature proportional to $ \lambda^2$ . Our results demonstrate the remarkable robustness of two-dimensional Ising criticality against this class of directional interactions.
Statistical Mechanics (cond-mat.stat-mech)
8 pages, 4 figures, 1 table, 2-page appendix
Iron-catalysed on-surface synthesis of substrate-decoupled graphdiyne monolayers
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Alice Cartoceti, Simona Achilli, Gianni Conti, Eliecer Pelaez-Sifonte, Alessio Orbelli Biroli, Francesco Sedona, Paolo D’Agosta, Francesco Tumino, Andrea Li Bassi, Jorge Lobo-Checa, Carlo S. Casari
Graphdiynes constitute an emerging class of two-dimensional sp-sp2 carbon allotropes with tunable electronic properties not accessible by graphene. Although flawless monolayer growth of graphdiyne networks has been attempted by means of on-surface synthesis protocols, the experimental realization of fully covalent and structurally ordered graphdiyne networks remains challenging due to the persistence of metalated intermediates and reaction byproducts, limiting the structural self-organization required for long-range covalent order. Here, we demonstrate that adding minute amounts of Fe atoms on the surface during the growth can exceptionally improve the synthesis of a covalent 2D graphdiyne monolayer framework on Au(111). By means of low-temperature scanning tunneling microscopy and spectroscopy, combined with density functional theory, we unveil the atomic-scale surface dynamics of the reaction. We demonstrate the crucial role of Fe atoms that bond with Br by-products, thereby forming Fe-Br species that promote the removal of Au adatoms and drive the conversion from a metalated network to a purely covalent framework upon mild annealing conditions. Moreover, we show the covalent graphdiyne network to be structurally and electronically decoupled from the underlying metallic substrate, revealing a finite bandgap of about 1.6 eV defined by the position of p_z frontier orbitals. These results establish a viable route for the atomically precise on-surface synthesis of all-carbon graphdiynes, and open the way to semiconducting 2D carbon materials complementing graphene.
Materials Science (cond-mat.mtrl-sci)
Light-tunable quantum metric non-linear Hall response in Berry dipole semimetals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-08 20:00 EDT
Debashree Chowdhury, Awadhesh Narayan
We investigate the effect of light on quantum metric-mediated intrinsic nonlinear Hall conductivity in Berry dipole semimetals. We discover that light induces a tunable asymmetry in the off-diagonal part of the quantum metric, which is manifested by an asymmetry in the quantum metric dipole. We show that the nonlinear response can be tuned directly by the light amplitude. In particular, we note that the direction of the nonlinear Hall signal changes when the light amplitude is increased beyond a threshold value. Light thus emerges as a promising stimulus to control the quantum geometric response in topological semimetals.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
6 Pages, 7 Figures
Phase lag enhances synchronization in coupled oscillators with inertia
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Sudo Yi, Cook Hyun Kim, Heetae Kim, B. Kahng
The second-order Kuramoto model with inertia exhibits different dynamical behaviors than the first-order KM without inertia. A central difference is its lower synchronization due to the emergence of multiple synchronized clusters with different frequencies. We aim to investigate how such lowered synchronization can be improved by applying external perturbations to the system in a steady state, for example, a symmetry-breaking phase lag to a subset of oscillators. We find that this phase lag steers the primary cluster along a specific path and enables it to merge with higher-order clusters, thereby enhancing global synchronization. Our results reveal a mechanism by which controlled phase lag can improve entrainment in inertial oscillator systems, with possible implications for synchronization control in inertial oscillator networks.
Statistical Mechanics (cond-mat.stat-mech), Chaotic Dynamics (nlin.CD)
7 pages, 3 figures
Nonlinear sigma models, antiperiodic boundary conditions, spin chains, and ‘t Hooft anomalies
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
We consider two sets of related models: initially, these are $ SU(2)$ antiferromagnetic spin chains with $ N$ sites of spin $ S$ , and the $ O(3)$ nonlinear sigma model in two dimensions with topological coefficient $ \Theta$ a multiple of $ \pi$ (and later, the extensions of these with any semisimple Lie group symmetry). It is known that, in a continuum description, the low-energy behavior of the spin chain is given by the sigma model with $ \Theta=2\pi S$ . We study these models with $ N$ odd and with antiperiodic (A) boundary condition (b.c.), respectively, which correspond. The A b.c. in the sigma model involves the $ \mathbb{Z}_2$ inversion symmetry $ \vec{n}\to-\vec{n}$ , and amounts to a flux of a $ \mathbb{Z}_2$ gauge field through a spacetime torus; summing over the two b.c.s for each direction would amount to gauging the $ \mathbb{Z}_2$ inversion symmetry. We show directly that, if and only if $ (-1)^{\Theta/\pi}=-1$ , the gauging cannot be carried out; there is an ‘t Hooft anomaly. The partition function for the A b.c. exists, but is not gauge invariant; consequently, the sum over b.c.s cannot be made modular invariant. The gauged model would be a sigma model with target space $ \mathbb{R}\mathbb{P}^2\cong \mathbb{S}^2/\mathbb{Z}_2$ , and hence this model does not exist for $ \Theta=\pi$ (mod $ 2\pi$ ). A related result is that, using semiclassical quantization, in the spin chain we obtain the known values of the ground-state crystal momentum, which at leading order depend only on $ N$ modulo $ 4$ and $ 2S$ modulo $ 2$ . For a large class of spin chains and associated sigma models we find similar results, but now $ (-1)^{\Theta/\pi}$ is replaced by the value $ \pm 1$ of the square of the time-reversal operator acting on a single spin, which is still determined by the coefficients of the topological terms, in a way that depends on the symmetry group.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
Unravelling the Role of Stacking Disorder on the Optoelectronic Properties of Zn3P2
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Francesco Salutari, Nico Kawashima, Aidas Urbonavicius, Helena Rabelo Freitas, Raphael Lemerle, Thomas Hagger, Kimberly A. Dick, Anna Fontcuberta i Morral, Simon Escobar Steinvall, Maria Chiara Spadaro, Silvana Botti, Jordi Arbiol
Zinc phosphide (Zn3P2) is a promising photovoltaic absorber for thin-film and flexible solar cells due to its earth-abundant composition and favourable optoelectronic properties. Recent advances in epitaxy have enabled the growth of high-quality Zn3P2 thin films despite the challenges posed by its incompatible lattice parameter and thermal expansion coefficient. However, Zn3P2 remains prone to intrinsic extended defects, such as rotated domains, that can limit device performance. Here, using (scanning) transmission electron microscopy, we identify a previously unreported class of extended defects that appear as planar faults described by displacement vectors lying in the (001) plane. Within a pseudo-cubic description of Zn3P2, we establish a direct correspondence between planar faults and rotated domains, showing that both arise from the flexible ordering of vacant sites in the Zn sublattice. First-principles calculations reveal an extremely low planar-defect formation energy of 2.5 mJ m-2, demonstrating that these defects form at essentially negligible energetic cost, in excellent agreement with their high experimentally observed occurrence. Additional density functional theory (DFT) calculations show that intrinsic planar defects neither introduce mid-gap electronic states nor significantly perturb the local electrostatic potential, indicating that they are electronically benign. Instead, we propose that planar defects indirectly degrade device performance by acting as preferential segregation sites for optically active point defects.
Materials Science (cond-mat.mtrl-sci)
34 pages
Cocktail effect and robust Berry curvature driven anomalous Hall conductivity in the entropy-stabilized Heusler alloy Co$2$(Ti${0.25}$V${0.25}$Cr${0.25}$Fe$_{0.25}$)Al
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Suraj Kushwaha, S. K. Panda, Sourav Marik, Kartik Samanta, Tirthankar Chakraborty
The interplay between chemical disorder and persistence of Berry curvature driven transport phenomena remains an important open question in entropy-stabilized systems. Here, we synthesize an entropy-stabilized Heusler alloy Co$ _2$ (Ti$ _{0.25}$ V$ _{0.25}$ Cr$ _{0.25}$ Fe$ _{0.25}$ )Al and systematically investigate its structural, magnetic, and magnetotransport properties using a combination of experimental measurements and density functional theory (DFT) calculations. The system crystallizes in cubic space group $ Fm\Bar{3}m$ and exhibits ferromagnetism with saturation magnetization in close agreement with the Slater–Pauling prediction. Transport and magnetotransport measurements reveal metallic behavior and a pronounced anomalous Hall effect with an anomalous Hall conductivity of approximately $ 134.4~ \Omega^{-1}$ .cm$ ^{-1}$ . Combined experimental observations and first-principles calculations establish that the anomalous Hall effect is predominantly intrinsic in origin and originates from the Berry curvature of the electronic bands. Remarkably, despite the substantial configurational disorder and the dilution of the constituent parent compounds, the anomalous Hall conductivity remains comparable to the largest values reported in the corresponding parent Heusler systems. This behavior reflects the manifestation of the cocktail effect, one of the core characteristics of entropy-stabilized systems. Our results also demonstrate that Berry curvature mediated transport persists in this chemically disordered system and indicates that entropy engineering can be a promising route for tuning intrinsic anomalous Hall responses.
Materials Science (cond-mat.mtrl-sci)
10 pages, 4 figures
Failure of the Quench Action Formalism for Mott Insulator Initial States
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-06-08 20:00 EDT
The quench action formalism relies on the assumption that the overlap between a generic initial state $ \left|\Psi_{0}\right\rangle $ and an eigenstate of an integrable model - defined through the rapidities $ \left|k_{1},…k_{N}\right\rangle $ - can be written as: \begin{equation} \left\langle k_{1},…k_{N}\mid\Psi_{0}\right\rangle =\exp\left(-S_{\Psi_{0}}\left(\rho\left(k\right)\right)\right),\label{eq:Exponential} \end{equation} where $ \rho\left(k\right)$ is the quasiparticle density of the state $ \left|k_{1},…k_{N}\right\rangle $ and $ S_{\Psi_{0}}$ is some smooth function of $ \rho\left(k\right)$ that depends on $ \Psi_{0}$ . In particular the quench action formalism assumes the overlap depends smoothly on the quasiparticle density $ \rho\left(k\right)$ . In this work, by explicit counter example, we show that this is not the case. We consider the quench between a Mott insulator and a Lieb Liniger gas. We show that the overlap between the ground state of the Mott insulator and arbitrary eigenstates of the Lieb Liniger gas has a highly singular behavior and no expression like Eq. (1) applies. We do so within the Tonks Girardeau limit of the Lieb Liniger gas and to leading order in the $ 1/c$ expansion for the overlap (with $ c$ being the coupling constant of the Lieb Liniger gas). In the Appendix we show similar results for overlaps in the XXZ model with crystal states.
Quantum Gases (cond-mat.quant-gas)
Comments are welcome
Skyrmions in Synthetic Antiferromagnets: Collapse and Nucleation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Magnetic skyrmions in synthetic antiferromagnets are promising nanoscale bits, but their usefulness depends on how reliably a written pair survives and can be created. Using a reduced lattice model, we compute minimum energy paths for collapse of an antiferromagnetically bound skyrmion pair and for reverse nucleation from a pinned antiferromagnetic reference state. With antiferromagnetically pinned boundaries, the main saddle energy changes only weakly with pinned-island size, whereas the skyrmion-pair minimum carries a strong size-dependent boundary penalty. For large pinned islands, collapse is layer-sequential and can pass through a single-layer skyrmion intermediate whenever this state satisfies the relaxation criterion. The much larger reverse barrier for nucleation shows a strong asymmetry with collapse in the same pinned-boundary model and is consistent with assisted layer-sequential writing.
Materials Science (cond-mat.mtrl-sci)
Enhanced viscous adhesion using deformable structure
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-08 20:00 EDT
Mary Williams, Thomas Desmedt, Fabian Brau, Pascal Damman
We investigate the adhesion dynamics of a thin elastic structure in contact with a viscous fluid and retracted at a controlled speed, mimicking natural adhesion mechanisms. During detachment, the viscous fluid confined between the deformable structure and a rigid substrate generates an adhesive force due to a pressure drop within the thin film. We show from dedicated experiments that the structural flexibility introduces a strongly nonlinear mechanical response, which significantly alters both the magnitude and the evolution of the adhesion force with retraction velocity. In contrast to rigid systems, the deformability of the structure enables enhanced and tunable adhesion. To capture this interplay, we develop a theoretical framework that couples elasticity and viscosity, providing new insights into how flexible structures enable adhesion control.
Soft Condensed Matter (cond-mat.soft)
Inverse Melting of 3D Antiferromagnetic Order in Multi-sublattice Magnetic Perovskites
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Bangye Qin, Dmitry D. Khalyavin, Ran Liu, Kazunari Yamaura, Alexei A. Belik, Roger D. Johnson
In conventional antiferromagnets a long-range ordered 3D ground state transitions to a disordered paramagnetic state on warming, often via lower dimensional spin correlations within the critical regime. Here we demonstrate a striking departure from this paradigm. Through analysis of neutron powder diffraction data, we show that the magnetic ground state of columnar-ordered quadruple perovskites, Na$ R$ Mn$ _2$ Ti$ _4$ O$ _{12}$ ($ R$ = Dy, Sm), lacks long-range order, hosting only 2D spin correlations. On warming, this disordered state transitions into a 3D long-range ordered antiferromagnetic structure prior to the phase transition to the paramagnetic state. Our results establish an unconventional order-by-heating mechanism in which intrinsic A-site chemical disorder is coupled to competing exchange interactions between the rare earth and Mn sub-lattices, leading to a novel type of magnetic phase transition.
Strongly Correlated Electrons (cond-mat.str-el)
Chromium chalcohalide Janus monolayer ferromagnets with perpendicular magnetic anisotropy and high Curie temperature
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
M. Bosnar, J.M. Lendinez, A.Yu. Vyazovskaya, I.Yu. Sklyadneva, R. Heid, S. V. Eremeev, U. Atxitia, S. Gallego, E.V. Chulkov, A. Arnau, M.M. Otrokov
Using density functional theory, we revisit the magnetic properties of a recently proposed family of noncentrosymmetric two-dimensional magnetic materials, chromium chalcohalide monolayers, CrXY (X=S, Se, Te; Y=Cl, Br, I). These systems consist of three atomic planes stacked in the X-Cr-Y sequence, which breaks inversion symmetry, giving rise to their designation as “Janus” monolayers. We consider both 1T and 1H structural polymorphs of CrXY. Among the two polymorphs, the 1T phase is consistently more favorable, with energy gains exceeding 0.55 eV per formula unit. Our total-energy calculations reveal that all dynamically stable CrXY monolayers exhibit ferromagnetic coupling. However, robust out-of-plane magnetic anisotropy is observed only in the CrSI and CrSeI compositions, for both 1T and 1H structures. The perpendicular magnetic anisotropy results from a constructive interplay between single-ion and anisotropic exchange contributions that overcome the dipole-dipole interaction. We further quantify the Dzyaloshinskii-Moriya interaction (DMI) in CrSI and CrSeI for both polymorphs, and reveal a weak-to-moderate DMI strength as compared to the isotropic exchange interaction term. Finally, for systems exhibiting ferromagnetic coupling and perpendicular magnetic anisotropy, the exchange and anisotropy parameters derived from density functional theory calculations are employed as inputs for large-scale atomistic spin dynamics simulations to probe the temperature evolution of real-space magnetic structures. The calculated Curie temperatures are at least 210 K for 1T-CrSI, 235-260 K for 1H-CrSeI, and 370-410 K for 1H-CrSI. In contrast, the sizable DMI in 1T-CrSeI results in a worm-like domain ground state at zero external field and enables the stabilization of skyrmions under a perpendicular magnetic field.
Materials Science (cond-mat.mtrl-sci)
Phys. Rev. B 113, 184425 (2026)
Phase diagram of the extended chequerboard $J-Q$ model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
The chequerboard $ J-Q$ model was proposed to describe the direct phase transition from the antiferromagnetic (AFM) state to the plaquette-sin glet (PS) solid state observed in SrCu$ _2({\rm BO}_3)_2$ . In this paper, we present a Monte Carlo study of the ground state of an extended ve rsion of this model. For all parameters investigated, we find only a direct first-order phase transitions from the AFM to the PS phase, with no intermediate phase between them. On the transition line, the system exhibits an emergent $ O(4)$ symmetry. Furthermore, we find that the Bi nder ratio of the columnar valence-bond solid state can be used to locate the phase transition. It exhibits a monotonic finite-size scaling b ehavior, allowing for a precise determination of the transition point.
Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 17 figures
Multiband superconductivity in the kagome-lattice superconductor Re2Zr
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-08 20:00 EDT
Gabriel Kuderowicz, Bartlomiej Wiendlocha
We present a first-principles investigation of the electronic structure, lattice dynamics, electron-phonon coupling, and superconducting properties of the hexagonal kagome-lattice compound Re$ _2$ Zr, in which time-reversal symmetry breaking and unconventional pairing have recently been proposed. We examine whether superconductivity in Re$ _2$ Zr can be explained within a conventional phonon-mediated framework by performing fully ab initio calculations within the density functional theory for superconductors. The electronic structure is characterized by a mixture of seven two- and three-dimensional Fermi surface sheets, giving rise to multiband superconductivity with many overlapping superconducting gaps. A spin-orbit-induced van Hove singularity is identified in the density of states near $ E_F$ . The electron-phonon interaction is moderately strong, with a coupling constant $ \lambda \simeq 0.88$ . Superconducting gap calculations reveal significant anisotropy and a broad distribution of gap values across different Fermi surface sheets. Spin fluctuations introduce additional depairing effects and reduce the critical temperature from 7.7 K to 6.4 K, in excellent agreement with the experimental value of 6.65 K. Taken together, our results show that the superconducting energy scale in Re$ _2$ Zr can be quantitatively reproduced within a conventional phonon-mediated framework, while the resulting state exhibits pronounced multiband and anisotropic gap structure. The origin of the experimentally suggested time-reversal symmetry breaking, however, remains an open question.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
13 pages, 11 figures + Supplemental Material. Accepted in Physical Review B
Asymmetry dynamics and nonequilibrium symmetry-breaking phase transitions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Liv Hammer, Colin Rylands, Federico Carollo
In classical settings, the Mpemba effect occurs when a hotter system cools faster than an initially colder one. In quantum systems, this effect can be reinterpreted exploiting the concept of symmetries, with the asymmetry of a subsystem playing the role of temperature. A quantum Mpemba effect arises when a more asymmetric state restores the symmetry faster than a less asymmetric one. Previous work mainly focuses on closed systems characterized by thermal equilibration and Hamiltonian symmetries. In this paper, we analyze the dynamics of asymmetry in an open quantum many-body system featuring symmetry breaking and uncover dynamical behavior that appears to be unique to these settings. In the symmetric phase, we demonstrate the existence of a quantum Mpemba effect, which emerges as a direct consequence of a non-monotonic evolution of the asymmetry. In the broken-symmetry phase, we analyze the imbalance between the system’s ability to increase or to decrease its asymmetry. Our results extend the notion of quantum Mpemba effects to open quantum many-body systems exhibiting symmetry-breaking phase transitions and establish them as a platform for observing and controlling anomalous relaxation phenomena.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
6+6 pages, 3+6 figures
On the true low-energy excitations of the three-dimensional spin glass
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-08 20:00 EDT
Claudio Chilin, Enzo Marinari, Víctor Martín-Mayor, Giorgio Parisi, Juan J. Ruiz-Lorenzo, David Yllanes
We study the low-energy excitations of the three dimensional spin glass through a large-scale Monte Carlo simulation on lattices up to $ L=18$ . We find smooth extrapolations down to zero temperature, which, in the case of the energy and of the link overlap, can be directly – and favourably – compared with previous investigations featuring ground states (i.e., at zero temperature). The best fit for the fractal dimension of the excitations is provided by Replica-Symmetry Breaking theory, but we also consider the alternative TNT description. The $ P(q)$ is found to verify the Parisi-Toulouse temperature scaling. Our data provides a spectacular confirmation of the overlap-equivalence hypothesis.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech)
27 pages, 6 figures
Squeezing dynamical singlets in bilayer nickelates
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Harrison LaBollita, Andrew J. Millis, Olivier Gingras
We present realistic calculations within the density functional plus cluster dynamical mean-field formalism indicating that the physics of the the bilayer Ruddlesden-Popper nickelates is to a significant extent controlled by interlayer “dynamical singlets’’ which are formed from the $ 3z^{2}-r^{2}$ orbitals singly occupied by electrons and are hybridized with itinerant planar $ x^{2}-y^{2}$ orbitals. The hybridization is found to respond differently to hydrostatic pressure and to epitaxial strain, capturing the experimentally observed dichotomy between bulk single crystals and epitaxial thin films and reproducing several experimental results including angle-resolved photoemission and transport measurements.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
5+7 pages, 4+7 figures
Ptychographic Algorithms for Phase Recovery in 4D Scanning Transmission Electron Microscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
In Momentum-resolved Scanning Transmission Electron Microscopy (4D STEM), a convergent electron beam is raster-scanned across a think specimen in 2D in real space. The corresponding 2D diffraction pattern, in momentum space, to each point is recorded, forming a 4D data set. Information decoding process can follow thereafter to produce an image of the specimen in real space. Ptychography is reconstruction algorithm that allow the extraction of the probe wavefunction and the multiplicative object transmission function of the specimen. Ptychography is implemented through direct and iterative schemes. Some of which are the extended Ptychographic Iterative Engine (ePIE), the Wigner Distribution Deconvolution (WDD) and the simpler version of WDD, the Single Side-Band (SSB). This thesis gives an overview of STEM ptychography giving examples of its experimental and simulated implementations. The different ptychographic reconstruction methods are explored in a mathematical framework when applicable. Finally, an SSB reconstruction was made using an original script for simulated data of MoS2 monolayer. Moreover, four-dimensional data was recorded using a STEM instrument. A natural step following this research would be the implementation of the WDD algorithm.
Materials Science (cond-mat.mtrl-sci), Instrumentation and Detectors (physics.ins-det)
Randomised mixed labyrinth fractals
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-08 20:00 EDT
Janett Prehl, Ligia Loretta Cirstea, Daniel Dick
In this paper, the class of randomised mixed labyrinth fractals is introduced. It is a class of finitely ramified Sierpinski carpets that generalize mixed labyrinth fractals. The structures are generated by randomly selected labyrinth patterns with fixed selection probabilities at each iteration level, offering a flexible framework to study fractal topology, arc dimensions, and shortest path properties. Here, the focus lies on analysing how the randomised mixing of patterns - specifically their shape, symmetry, and path geometry - effects arc dimensions, path lengths, and isotropy restoration. The study reveals that isotropy, previously shown for self-similar fractals, extends to the randomised mixed class. Various scaling behaviours of shortest path dimensions with respect to the mixing probability are identified, including linear and nonlinear monotonic trends, as well as transitions with maxima. The approximated path matrix is proposed as an efficient alternative to extensive iterative simulations, reliably reproducing statistical results. The findings highlight the relevance of pattern properties in determining fractal structures and dynamics and suggest applications in physical systems such as diffusion, signal processing, and antenna design.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Mathematical Physics (math-ph)
25 pages, 16 figures, 3 tables
Theory of learning of high-dimensional controlled non-linear dynamical systems (I): models and methods
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-08 20:00 EDT
Neural ordinary differential equations (neural ODEs) have rapidly gained prominence as a powerful and unifying framework for conceptualizing artificial neural networks, elegantly connecting the continuous-time modeling of dynamical systems with the discrete, data-driven paradigm of modern deep learning. Beyond their practical advantages they offer fresh theoretical insights into the training and generalization properties of neural networks. The distinctive feature of this framework is its dual dynamical nature: inference dynamics, which govern the ODE evolution during forward computation, and training dynamics, which control the optimization of model parameters. This makes neural ODEs a particularly well-suited theoretical framework for studying a large variety of settings such as multi-layer neural networks (ResNets for example), autoregressive models (with next-token generation dynamics), generative models, and recurrent neural networks in theoretical neuroscience. In this work, we introduce a theoretically grounded class of models for studying neural ODEs trained via online stochastic gradient descent. We solve the training dynamics of these models via dynamical mean field theory and derive learning curves in the high-dimensional limit.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech), Machine Learning (stat.ML)
28 pages, 2 figures
Towards Engineering Material Neural Networks
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Charles de Kergariou, Hortense le Ferrand, Ali Momeni, Romain Fleury, Kunal Masania, Adam W Perriman, Fabrizio Scarpa
Structures that capture functionality in the form of animate or intelligent machines have the potential to transform modern engineering applications. Animation and embedded intelligence are typically realised by integrating advanced capabilities such as reversibility, adaptive responses and learning directly into the materials themselves. Currently, the majority of adaptive material systems rely on predefined adaptive designs combined with in-service, electronics-based computing to dynamically modify the structural behaviour. However, structural configurations with interconnected adaptable nodes are able to approximate continuous functions, providing new possibilities and opportunities than classical metamaterials and computational materials. We discuss here the potential to design load-bearing engineering materials with trainable physical parameters and neural network-inspired morphologies, embedding intelligence directly into their structure, a concept we define as Engineering Material Neural Networks (EMNNs) as a subcategory of Physical Neural Networks. In this perspective, we first establish the foundational concept of EMNNs; we then detail the mechanical and multifunctional properties required for such structural configurations. Finally, we evaluate existing and emerging engineering materials that hold promise for enabling this innovative approach. Key material candidates for realising EMNNs include composites, architected, biological and engineering living materials. We also outline future directions in materials science and structural engineering for developing EMNNs.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn)
37 pages, 8 pages
Oscillatory-nonnormal decomposition of dissipation in Ornstein-Uhlenbeck processes
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Ryuna Nagayama, Artemy Kolchinsky, Sosuke Ito
We provide a decomposition of the steady-state entropy production rate associated with an Ornstein-Uhlenbeck process into two contributions: one associated with oscillatory behavior and one associated with nonnormality. We also show that each contribution is associated with a different fundamental trade-off. The oscillatory contribution leads to the dissipation-coherence trade-off for noise-induced oscillations, which bounds the entropy production per oscillatory period by the number of oscillations within one correlation time. Notably, the trade-off is twice as strict as those conjectured or derived for other systems. The nonnormal contribution leads to a trade-off between entropy production and acceleration of relaxation. We also demonstrate the decomposition using a simple bead-spring model.
Statistical Mechanics (cond-mat.stat-mech)
10 pages, 1 figures (main text) + 7 pages (supplemental material)
Vortex dynamics in rotating dipolar supersolids across Josephson and self-trapping regimes
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-06-08 20:00 EDT
Aitor Alaña, Michele Modugno, Pablo Capuzzi
We investigate vortex nucleation and transport in a rotating dipolar supersolid arranged in a triangular droplet lattice, exploiting its description as an array of weakly linked condensates. By considering both Josephson and macroscopic self-trapping dynamics, we show that local phase differences between droplets provide a compact and highly predictive framework to explore a wide range of vortex behaviors. In particular, Josephson oscillations can be devised to induce vortex nucleation and motion near the vertices of the low-density hexagonal lattice (between droplets), while self-trapping dynamics induce running phases that enable directed vortex transport, which may be accompanied by vortex-antivortex pair creation and annihilation over finite time scales. Comparison with simulations based on the extended Gross-Pitaevskii equation demonstrates that a three-droplet description is essential to capture vortex motion near hexagon vertices. Together, Josephson and self-trapping dynamics provide a tunable protocol to trigger and track vortex nucleation, transport, and vortex-antivortex pair annihilation, revealing the microscopic topological mechanisms underlying phase slips in rotating dipolar supersolids.
Quantum Gases (cond-mat.quant-gas)
10 pages, 10 figures
Peculiarities Of Phase States In N2O-CO2 Cryoalloys According To Electron Diffraction Data
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
A. A. Solodovnik, O. P. Konotop
The structural characteristics of n2o-co2 alloys have been studied using transmission electron diffraction (THEED) across the entire range of their mutual concentrations at temperatures of 5 K and 65 K. The ranges in which regular solutions exist and intervals of alloy phase separation have been identified using the dependence of lattice parameters on composition and profile analysis of the diffraction pattern intensity distribution. It was found that maximum solubility values are up to 11 mol.% CO2 in the N2O matrix and up to 30 mol.% n2o in solid co2 at 65 K. The solubility limits for the components at 5 K are less 20 mol.% co2 in crystalline n2o and less than 35 mol.% n2o in a co2 crystal lattice. It was established that the character of n2o-co2 alloy separation corresponds to the mechanism of spinodal decomposition. The relative excess volumes that pertain to the admixture were determined for the CO2 impurity in solid n2o and for n2o impurity in co2 crystal. Conclusions regarding the character of n2o-co2 phase diagram have been made.
Materials Science (cond-mat.mtrl-sci)
20 pages, 5 figures
Modelling time-irreversible avalanches
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Andrea Baldassarri, Andrea Puglisi
We investigate the problem of the time reversal symmetry of fluctuations, as witnessed by the average shape of avalanches. This quantity has been measured in a variety of systems, ranging from magnetic materials to earthquakes. Although an asymmetric shape is often observed, which is a signature of a non-equilibrium dynamics, there is no general theoretical control of this feature. In this paper, we propose a non equilibrium extension of a paradigmatic model for ``crackling-noise’’, the so called ABBM model. Our model is strictly related to the Brownian Gyrator, which has been previously introduced in stochastic thermodynamics as the simplest model for thermal anisotropy, but it can also be framed in the context of rate-and-state models. It reproduces the phenomenology observed in experiments on granular friction, and allows for a systematic theoretical study of the asymmetry. We manage to correlate a measure of asymmetry, that can be easily computed in experiments, with the entropy production rates of the dynamics.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn)
9 pages, 6 figures + SI (2 pages, 1 figure)
Topological Anderson insulators and reentrant topological transitions in a quasiperiodic long-range Su-Schrieffer-Heeger model
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-08 20:00 EDT
We study a one-dimensional long-range Su-Schrieffer-Heeger model with third-nearest-neighbor hopping and subject to quasiperiodic disorder. In the clean limit, the model hosts phases characterized by winding numbers $ W=-1,0,1$ and $ 2$ . The introduction of quasiperiodic disorder profoundly modifies the phase diagram and induces a series of topological phase transitions. Owing to the competition between topological dimerization and localization, topological Anderson insulating (TAI) phases with different winding numbers emerge and can persist even when the spectral gap becomes nearly closed in the strong-disorder regime. In addition, we uncover multiple reentrant topological phase transitions induced by varying either the quasiperiodic disorder strength or the hopping amplitudes. Remarkably, the system exhibits staircase-like topological Anderson transitions, where the real-space winding number evolves through successive quantized steps with increasing disorder strength. Our results demonstrate that the interplay between long-range hopping and quasiperiodic disorder generates a rich landscape of disorder-induced topological phases and reentrant topological transition phenomena.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
9 pages, 6 figures
Microswimmers create bicontinuous emulsions in binary fluids
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-08 20:00 EDT
Harinadha Gidituri, Sotiris Samatas, Juho S. Lintuvuori
We consider a generic case of neutrally wetting microswimmers in symmetric mixtures of two phase separating fluids, using hydrodynamic simulations. The swimmers spontaneously emulsify the two fluids into bicontinuous foam-like state. The two principal activity components: source dipole (self-propulsion) and force dipole (active mixing), create a twofold mechanism to stabilise the structures. When the self-propulsion is too strong, the swimmers cross the interfaces rapidly and the two fluids will phase separate. Below this threshold, the active stresses from the force dipoles, stabilise a dynamic and bicontinuous foam-like state. When the activity is turned off, the system relaxes into a kinetically trapped bicontinuous state, with particles permanently trapped at the interfaces. Our results provide a microscopic route to tunable active emulsions, with implications for bacterial suspensions and synthetic active matter.
Soft Condensed Matter (cond-mat.soft), Fluid Dynamics (physics.flu-dyn)
6 pages, 6 figures
Flexible PDMS/La${0.7}$Sr${0.3}$MnO$_3$/MWCNT Composite Thin Films for Multifunctional Temperature and Magnetic Sensing Electronic Skin
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Jimlee Patowary, G. Suresh, Jitendra Kumar, Ashutosh Kumar
The development of multifunctional electronic skin (e-skin) requires materials that combine mechanical flexibility with responsiveness to multiple stimuli. In this work, a flexible PDMS/La0.7Sr0.3MnO3 (LSMO)/MWCNT composite thin film was fabricated via solution casting, using LSMO powder synthesized by a solid-state reaction method. Structural and spectroscopic analyses confirm the formation of single-phase rhombohedral LSMO and successful incorporation of PDMS, LSMO, and MWCNT components. The composite exhibits a smooth and uniform surface morphology, along with significantly enhanced thermal stability, retaining ~70% mass at elevated temperatures. Electrical measurements reveal thermally activated resistivity behavior, enabling temperature sensing functionality. Additionally, the composite shows a notable decrease in resistance under an applied magnetic field, exhibiting magnetoresistance due to spin-dependent transport in the LSMO phase. Mechanical testing indicates elastomeric behavior with a maximum load of ~0.49 N and stretchability of ~26%, along with ductile deformation characteristics. The multifunctional sensing properties arise from the synergistic interaction between the conductive MWCNT network and magnetically active LSMO within the flexible PDMS matrix. Overall, the composite demonstrates a unique combination of thermal stability, mechanical flexibility, and dual sensing capability, making it a promising material for next-generation e-skin applications.
Materials Science (cond-mat.mtrl-sci)
11 Pages, 8 Figures, 2 Tables
How Similar Can Fractional Chern Insulators Be to Fractional Quantum Hall States? Moiré-Enhanced Gaps and Excitation-Spectrum Correspondence
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Siddhartha Sarkar, Yitong Zhang, Kai Sun
Fractional Chern insulators (FCIs) realize fractional quantum Hall topology in lattice bands, but their excitation spectra remain far less understood than their ground states. Here we establish a theoretical principle relating the periodic electron-density modulations of flat Chern bands to the many-body gap and excitation spectrum of FCIs. Contrary to the conventional view that such density modulations are detrimental to fractional topology, we show that different reciprocal-lattice Fourier components play sharply distinct roles: components at smaller reciprocal lattice vectors suppress the FCI gap, whereas components at larger reciprocal lattice vectors enhance it. By suppressing the harmful small-wave-vector components and amplifying the beneficial large-wave-vector components, the gap enhancement can, in principle, be made arbitrarily large within the projected flat-band theory. Moreover, the same enhancement factor rescales the full low-energy spectrum, making the FCI excitation spectrum predictable from the corresponding Landau-level problem. We further generalize this correspondence to non-Abelian states. Applying this principle to moiré Chern bands, we identify these reciprocal-lattice density components as practical diagnostics for robust FCIs.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Six Open Questions in Machine-Learned Interatomic Potential Foundation Models
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Isabel Creed, Tim Rein, Ingvars Vitenburgs, Wojciech G. Stark, Viktor Ellingsson, Ahmed Y. Ismail, Guangyu Liu, Yuchen Lou, Bradley A. A. Martin, Cyprien Bone, Matthew A. H. Walker, Mueen Taj, Shirui Wang, Kelvin Wong, Ruiqi Wu, Prakriti Kayastha, Bingqing Cheng, Aditi Krishnapriyan, Michele Ceriotti, Marcel F. Langer, Jarvist Moore Frost, Alex M. Ganose, Venkat Kapil, Keith T. Butler
Machine-learned interatomic potentials (MLIPs) have had a profound impact on molecular modelling in recent years, promising to resolve the long-standing tension between the scale and accuracy of simulations. There has been a proliferation of new models and designs, and recently the paradigm of ``foundational’’ MLIPs has become prevalent. Broadly speaking, foundation models are trained on large diverse datasets and promise to work well for new systems with minimal updates required. However, in such a new and fast moving field, there are many unanswered questions. In this article, we set out to articulate and explore what we see as the most important among these questions. We start by developing a working definition for foundational MLIPs and use this definition to frame the subsequent open questions. Despite the rapid progress in the field of MLIP models, we believe that these are fundamental questions which will continue to define cutting edge research in MLIPs in the years to come.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn), Applied Physics (physics.app-ph), Computational Physics (physics.comp-ph)
Direct High-Magnetic-Field Coupling to Stripe Order in a Cuprate Superconductor
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
Leonardo Martinelli, Izabela Biało, Jens Oppliger, Julia Küspert, Orion Gerguri, Sandro Brunner, Benedikt Eggert, Mark H. Fischer, Jochen Geck, Marein Rahn, Ellen Fogh, Jaewon Choi, Atsuhiko Miyata, Oleksandr Prokhnenko, Zahirul Islam, Fernando Igoa Saldaña, Martin v. Zimmermann, Rachel Nickel, Kurt Kummer, Nicholas B. Brookes, Adheena Painganoor, Paola Caterina Forino, Rasmus Toft-Petersen, Niels Bech Christensen, Xunyang Hong, Qisi Wang, Tohru Kurosawa, Naoki Momono, Migaku Oda, Dmitri V. Novikov, Azat Khadiev, Thomas Herrmannsdörfer, Ana Kurtanidze, Katharina Ollefs, Zuzana Konôpková, Michał Andrzejewski, Minxue Tang, Ulf Zastrau, Alexander Pelka, Hauke Höppner, Jolanta Sztuk-Dambietz, Vratko Rovensky, Torsten Laurus, Erik Brambrink, Björn Näser, Marcin Sikora, Cornelius Strohm, Carsten Baehtz, Shingo Yamamoto, Johan Chang
Superconductivity in cuprates emerges out of a complex normal state that hosts density waves, pseudogap physics, and strange metal properties. Here, we access this normal state by synchronizing free-electron laser x-rays with high-magnetic-field pulses up to 44 T. We observe a linear increase in charge order amplitude and correlation length that persists far above the vortex melting transition. This behavior is incompatible with standard phase competition between charge order and superconductivity. By means of conventional hard x-ray diffraction and magnetostriction, we show that applied fields also enhance monoclinic lattice distortions. However, this magnetoelastic response is weaker and an epiphenomenon of the stripe order enhancement. Combined with recent observations of field-linear spin freezing, our results point to a direct coupling between magnetic field and the spin component of stripe order in the high-field normal state – a mechanism independent of superconductivity suppression that has so far remained hidden from scattering probes.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
3 figures
Resolving Light-Induced Structural Rearrangements in Responsive Microgels
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-08 20:00 EDT
Fabrizio Camerin, Megha Emerse, Gianpaolo Gallo, Najet Mahmoudi, Gregory Smith, Emanuela Zaccarelli, Lucio Isa, Marco Laurati, Jacopo Vialetto
Optically-responsive microgels offer a versatile platform for designing adaptive soft materials with coupled light and thermal responsiveness. Control over the crosslinking degree is particularly appealing as it can regulate not only particle size but also stiffness, thereby enabling remote tuning of key material functionalities. However, the internal structural changes that couple molecular photoresponsive mechanisms to mesoscopic properties remain poorly resolved. Here, we investigate different light-responsive microgels containing covalently incorporated coumarin moieties, which impart optical sensitivity through UV-induced cycloaddition, by combining dynamic light scattering, small-angle neutron scattering, and molecular dynamics simulations. We show that light irradiation alters not only particle size but also the internal polymer density distribution and subsequent thermal response. Before irradiation, the microgels exhibit a star-like architecture with a dense core and extended polymeric arms. After irradiation, the network evolves toward a markedly more compact structure. This transformation cannot be rationalized simply as an equivalent to an increase in crosslinking density during synthesis, as observed in the thermal response, revealing light as a powerful tool to regulate microgel architecture and multifunctional responsiveness.
Soft Condensed Matter (cond-mat.soft)
Topologically Enforced Lifshitz Multicriticality in One Dimension
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Recent advances have revealed that topology can further enrich the universality classes of quantum phase transitions, thereby extending beyond the traditional paradigms of statistical and condensed matter physics. However, multicriticality between topologically distinct quantum critical lines remains insufficiently explored. In this Letter, we systematically construct and investigate a novel class of topologically enforced Lifshitz multicritical points in one dimensional chiral symmetric fermionic systems. Such multicriticality is driven solely by changes in the topology of neighboring critical lines, beyond previously recognized multicritical points that are typically induced by changes in critical exponents. More importantly, the topologically enforced multicriticality identified here can host robust topological degeneracies while surprisingly exhibiting a breakdown of the Li Haldane bulk boundary correspondence-a phenomenon we elucidate through a simple physical picture.
Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
4.5 pages + 20 pages, 11 figures. Any comments or suggestions are welcome!
Hydrogel mechanics below swelling equilibrium
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-08 20:00 EDT
A. Chao Correas, Y. Feng, R. W. Style, D. S. Kammer
Hydrogels are versatile materials due to their softness and ability to undergo large changes in water content. Their mechanics, however, are complex, being a tight coupling between fluid flow and elastic deformations. We use experiments and theory to show that this coupling simplifies when hydrogels are not fully swollen. In this regime, polymer-water affinity controls local hydration, while the much weaker polymer network elasticity plays a secondary role, setting the resulting elastic shape. This observation enables a simplified model that accurately predicts stresses and deformations.
Soft Condensed Matter (cond-mat.soft)
Polar and quadratic magneto-optical Kerr effects in nonmagnetic/ferromagnet bilayers for spin-orbit torque measurements
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-08 20:00 EDT
Yukihiro Marui, Masashi Kawaguchi, Kohji Nakamura, Masamitsu Hayashi
Recent studies have revealed that spin Hall magnetoresistance (SMR) contributes to both the anomalous and planar Hall resistances in nonmagnetic metal (NM)/ferromagnetic metal (FM) bilayers. This effect becomes pronounced when the NM layer exhibits a large spin Hall angle, as in W/CoFeB bilayers. In such systems, the ratio of planar to anomalous Hall resistances, normally small in single CoFeB layers, can approach unity. This unusually large ratio complicates the determination of spin-torque efficiency using harmonic Hall voltage measurements. To overcome this limitation, magneto-optical Kerr effect (MOKE) measurements have been proposed as an alternative approach. Here, we investigate the polar and quadratic MOKE components, which correspond to, respectively, the anomalous and planar Hall resistances in the low-frequency limit to clarify whether the MOKE measurements are suitable for characterizing the spin-torque efficiency. We find that the ratio of quadratic to polar MOKE signals in NM/FM bilayers is significantly smaller than the corresponding Hall resistance ratio, indicating that SMR contributes negligibly to the MOKE response in the visible range. Consequently, the spin-torque efficiency extracted from MOKE measurements agree well with those expected from the spin Hall angle of the NM layer. These results clarify the reason why MOKE measurements provide reliable determination of the spin-torque efficiency.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Phys. Rev. B 113, 214419 (2026)
Scalable Prediction of Complex Surface Reconstructions under Operating Conditions via Harmony-Search-Based Global Optimization
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
The dynamic structural evolution of catalyst surfaces under operating conditions dictates catalytic performance, yet capturing these reconstructions atomically remains challenging. Global optimization based on machine learning interatomic potentials (MLIPs) is promising, but scaling to large-scale, low-symmetry operando systems is hindered by expansive search spaces and potential energy surface (PES) inaccuracies. Herein, we present Harmony-search-based Atomic Structural Global Optimization (HASGO), a framework integrating universal MLIPs with a harmony search algorithm. HASGO overcomes the problem of PES softening by incorporating a multi-head replay fine-tuning protocol. Moreover, the stochastic structural perturbation step in its algorithm offers a fault-tolerant strategy to enhance the robustness of global convergence. These enable HASGO to identify intricate surface oxide overlayers that align with atomic-resolution microscopy, thereby resolving the square-pyramidal subsurface O5 motif on Ag(100) during ethylene epoxidation. This scalable framework provides a robust approach for uncovering operando structures, accelerating the rational design of industrial catalysts.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
Near-room-temperature magnetoelectric coupling engineered through inversion-breaking tilts in a bulk perovskite polytype
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-08 20:00 EDT
Struan Simpson, Urmimala Dey, Martin R. Lees, Ivan Da Silva, Nicholas C. Bristowe, Mark S. Senn
Systematic strategies to design properties such as ferroelectricity or magnetoelectric coupling are well established in simple perovskite materials, but they remain scarce in more complex framework structures. Using a hexagonal polytype of the ternary manganite AMnO3 (A = Ba, Sr, Ca) as a model system, we introduce a symmetry-guided design principle in which an inversion-breaking rigid-unit mode (RUM) serves as a single structural instability generating both polar and ferromagnetic orders within a bulk material. Symmetry analysis and first-principles calculations reveal that co-operative tilts of the Mn2O9 bioctahedral dimers generate both a spontaneous polarization and a ferromagnetic moment. High-resolution diffraction and magnetic susceptibility measurements show the structural and magnetic orders persist as high as 450 K and 280 K, respectively, highlighting the untapped potential of framework structures which deviate from simple perovskite motifs to be designed to host useful ferroic properties. Our approach establishes a transferable symmetry-based framework to engineer ferroelectric and magnetoelectric states across chemically diverse framework architectures.
Materials Science (cond-mat.mtrl-sci)
Main text: 30 pages, 5 figures. SI: 32 pages, 19 figures
Fermion sign problem and the structure of Lee-Yang zeros. II. Finite temperature results for a model system without interactions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-08 20:00 EDT
Ran-Chen He, Jia-Xi Zeng, Shu Yang, Cong Wang, Qi-Jun Ye, Xin-Zheng Li
Beyond the analysis of the Lee-Yang (LY) zero of $ \xi$ at $ 0$ K presented by our previous work [He et. al. Phys. Rev. E 113, 24115 (2026)], it is important but intricate to understand how these zeros evolve with temperature ($ T$ ). Here, we use an analytically solvable noninteracting one-dimensional particle-on-a-ring model to address this. We determine the trajectories of these zeros and analyze how their evolution with $ T$ reshapes the analytic structure of the partition function. In particular, the zero originating from $ \xi=-1$ at $ T=0$ remains close to $ -1$ at low $ T$ , where it governs the sign factor and strongly constrains continuation along the real $ \xi$ axis. This explains why both direct extrapolation and implicit schemes such as contour-based fitting can fail in the low-$ T$ regime, even at high fitting order, while becoming reasonable again once the relevant zeros move away at higher $ T$ s. Furthermore, based on the polynomial structure of the partition function, we propose a new fitting strategy for low-$ T$ fermionic properties. The key is to first obtain reliable high-$ T$ fermionic properties by continuing sign-problem-free data in $ \xi\in[0,1]$ to $ \xi=-1$ , and then extend this information toward lower $ T$ through $ T$ -fitting of the $ \xi$ -independent remainder $ \phi(\beta)=Z_{\text{F}}$ . These results provide a solvable benchmark for diagnosing the validity of analytic continuation and suggest a possible route toward treating more realistic interacting fermionic systems.
Statistical Mechanics (cond-mat.stat-mech)
Flow of deformable droplets: self-pinned glasses and string-like flow
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-08 20:00 EDT
Achille Quarante, Michael Chiang, Davide Marenduzzo, Giuseppe Negro
We investigate, through numerical simulations, the rheology of a dry suspension of deformable droplets under pressure-driven flow. The system exhibits two force-driven dynamical transitions. At low forcing, the suspension behaves as a yield-stress material: below a critical force, droplets remain arrested in an amorphous solid-like state. Our simulations suggest that yielding is controlled by droplet contacts and predict that the critical force strongly depends on deformability. Above yielding, the suspension does not flow steadily but rather enters an intermittent, stick-slip regime characterised by long-lived caging and non-Gaussian velocity fluctuations. This state can be interpreted as a “self-pinned’’ glass, in which slowly evolving droplet overlaps generate an effective rugged energy landscape that dynamically traps droplets and produces intermittent rearrangements reminiscent of near-critical dynamics in depinning models. At larger forcing, droplets deform sufficiently to continuously exchange neighbours, progressively annealing the overlap structure and driving a dynamic transition to a string-like, flowing state. Our results identify the restructuring of overlap networks as a generic mechanism which controls flow in driven suspensions of deformable particles.
Soft Condensed Matter (cond-mat.soft)
Bulk Superconductivity driven by Disorder-Induced Delocalization in 4Hb-Ta(S$_{1-x}$Se$_x$)$_2$
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-08 20:00 EDT
Lu Chen, Sae-Hee Ryu, Avior Almoalem, Yuanqi Lyu, Koh Yamakawa, Luke Pritchard Cairns, Ryan Day, Ehud Altman, Daniel Podolsky, Dung-Hai Lee, 4 Vidya Madhavan, Eli Rotenberg, James G. Analytis
The unconventional superconductor 4Hb-TaS$ _2$ is a natural heterostructure that can be broadly understood as interleaving Mott-like and metallic layers. We study the properties of this material as a function of quenched disorder in the form of Se/S substitution and find that while disordered samples show bulk superconductivity, clean samples do not. We show that a disorder-driven delocalization of carriers in the Mott-like ($ 1T$ -) layer forms a new Fermi surface that is absent in the cleanest samples. This suggests that one of the primary drivers for superconductivity is the fragility of the Mott state, whose delocalization brings to life a sea of strongly correlated electrons.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
17 pages, 5 figures in the main text
Non-Abelian braiding in Abelian Fractional Quantum Hall Phases from realistic interactions
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-08 20:00 EDT
We propose a method of realizing non-Abelian braiding of fractionalized quasiholes in the Laughlin fractional quantum Hall phase at $ \nu=1/3$ with realistic two-body interactions within the lowest Landau level. It is numerically shown that low-lying gapped excitations near $ \nu=1/3$ are contained almost entirely within the null space of the three-body Moore-Read model Hamiltonian. They are thus quantum fluids of non-Abelian quasiholes that are in principle physically accessible. In particular, Laughlin ground state can be described as a fluid of $ \psi$ -type" quasiholes formed by binding a magnetic flux with a Majorana fermion (MF), and the Laughlin quasiholes are described by the $ 1$ -type’’ quasiholes, which are magnetic fluxes without a MF attached. Within the Laughlin phase, Laughlin quasiholes can be locally fractionalized into non-Abelian quasiholes, when the strong attraction between them is overcome by properly designed one-body electronstatic trapping potentials. Extensive numerics with proper finite-size scaling corroborate this physical picture, and our study points to the possibility of realizing non-Abelian braiding within an Abelian topological phase in experiment without the need for fine-tuning realistic electron-electron interaction.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
comments very welcome