Mesoscale and Nanoscale Physics
Sub-diffraction-resolved spatial distribution of emitting excitons in STM-induced luminescence of 2D semiconductors via Richardson-Lucy deconvolution
Elysé Laurent, Ricardo Javier Peña Román, Sarah Miller et al. (+7 more)
Using scanning tunneling microscopy-induced luminescence (STML), the optical properties of two-dimensional (2D)
semiconductors may be investigated at the nanoscale. This is possible because the tunneling current under the tip is an extremely localized electrical excitation source. However, in most STML applications, the spatial distribution of the emission relative to the excitation point is unresolved. Yet this distribution contains key information about how the interaction of
excitons with injected charge carriers affects the luminescence of these materials, and about
exciton transport. Resolving this spatial distribution at the nanoscale is relevant both for a fundamental understanding of
exciton physics and for device applications; yet it remains a significant challenge. In this work, we resolve the spatial distribution of the emission beyond the diffraction limit of light by deconvolving real-space optical microscopy images of the STML using an iterative
algorithm, i.e., Richardson-Lucy (RL) deconvolution. To showcase this technique, we apply it to the STML of monolayer tungsten diselenide ($\mathrm{WSe_2}$) and tungsten disulfide ($\mathrm{WS_2}$). Thus, we highlight hitherto ignored or misunderstood aspects of STML on 2D
semiconductors related to
exciton and charge carrier transport, namely the dependence of the spatial distribution of emission on the tunnel current setpoint and the origin of the emission from hot spots located micrometers from the excitation source.
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All authors Elysé Laurent, Ricardo Javier Peña Román, Sarah Miller, Aditi Raman Moghe, Etienne Lorchat, Séverine Le Moal, Elizabeth Boer-Duchemin, Luiz Fernando Zagonel, Stéphane Berciaud, Eric Le Moal
Disordered Systems and Neural Networks
Rheological Parameter Identification in Granular Materials Using Physics-Informed Neural Networks
Barbara Baldoni, Mickaël Delcey, Yoann Cheny et al. (+3 more)
Physics-Informed Neural Networks (PINNs) have recently emerged as a promising tool for fluid dynamics, particularly for flow reconstruction and parameter identification. In the context of granular media, accurately estimating rheological parameters remains a major challenge, as it typically requires complex and costly experimental setups. In this work, we propose a PINN-based approach to identify key rheological parameters of granular materials using a simple experiment: the granular column collapse. A proof of concept is presented using synthetic data, where the PINN is trained to infer the flow fields while simultaneously recovering the rheological parameters. Beyond parameter identification, the method also enables reconstruction of the pressure field, which is difficult to access experimentally. The results highlight the potential of PINNs for data-driven rheometry of granular materials and open perspectives for future applications with real experimental data.
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All authors Barbara Baldoni, Mickaël Delcey, Yoann Cheny, Adrien Gans, Mathieu Jenny, Sébastien Kiesgen de Richter
Mesoscale and Nanoscale Physics
An extended low-frequency noise compact model for single-layer graphene FETs including correlated mobility fluctuations effect
Nikolaos Mavredakis, Anibal Pacheco-Sanchez and David Jimenez
Correlated mobility fluctuations are considered in the physics-based carrier number fluctuation deltaN low-frequency noise (LFN) compact model of single-layer
graphene field effect transistors (GFET) in the present study. Trapped charge density and Coulomb scattering coefficient deltaN LFN parameters are obtained after applying a parameter extraction methodology, adapted from conventional silicon technologies, to the linear ambipolar regions of GFETs. Appropriate adjustments are considered in the method according to GFETs physical characteristics. Afterwards, Hooge mobility as well as series resistance fluctuations LFN parameters can be extracted. The updated LFN model is validated with experimental data from various long and short-channel GFETs at an extended range of gate and drain bias conditions.
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Materials Science
Chiral-phonon generation of orbital currents in light transition metals
Marc Rovirola, Júlia Òdena, Anna Castellví et al. (+10 more)
Orbital angular momentum offers a new channel for information transport in a vast set of materials. Its coherent generation and detection remain, however, largely unexplored. Here, we demonstrate that
chiral surface acoustic waves (SAWs) generate sizable orbital currents in light-metal/ferromagnet
bilayers through both the acoustic orbital
Hall effect and acoustic orbital pumping. Using
symmetry analysis of SAW-driven voltages, we disentangle vorticity-sensitive orbital currents arising from
lattice rotation in the non-
magnetic layer from angular-momentum pumping from the ferromagnet. Strong signals are observed only in nickel/chromium and nickel/titanium, while nickel/aluminum and all cobalt-based
bilayers show negligible responses, revealing the critical roles of orbital
Hall conductivity,
phonon-orbital coupling, and interfacial orbital transparency. Comparison with
spin-torque
ferromagnetic resonance and second-harmonic measurements – where electrically driven orbital angular momentum are weaker – demonstrates that
phonon excitation generates orbital currents more efficiently. These results establish
chiral SAWs as an effective route for orbitronic functionality and open pathways toward
phonon-controlled orbital magnetism.
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All authors Marc Rovirola, Júlia Òdena, Anna Castellví, Quim Badosa, Blai Casals, Adrián Gudín, Haripriya Madathil, Fernando Ajejas, Paolo Perna, Alberto Hernández-Mínguez, Joan Manel Hernández, Saül Vélez, Ferran Macià
Materials Science · Cross-listed from physics.optics
Dielectric permittivity tensor dynamics of in-plane hyperbolic van der Waals MoOCl2 and emergent chiral photonic applications
Artsruni Margaryan, Maksim Sargsyan, Meri Hayrapetyan et al. (+3 more)
Van der Waals (vdW)
crystals offer unique opportunities for modern nanophotonic applications owing to their intrinsic anisotropic nature. While most of them exhibit uniaxial anisotropy arising from weak out-of-plane vdW interaction, some of their representative families also exhibit an in-plane biaxial anisotropy. Among the latter, outstand vdW oxochlorides with in-plane axes of a different physical character (metallic or dielectric). Here, we present an accurate dynamics of dielectric permittivity tensor components of vdW MoOCl2 in the ultraviolet (UV) to visible (Vis) spectral region partly covering near-infrared (NIR). Addressing its enormously anisotropic optical constants, we focus on another hyperbolicity window of vdW MoOCl2 emerging in the UV spectral region that may potentially unlock rich light-matter interaction effects. Furthermore, we propose an approach towards designing nanoscale handedness preserved Vis light circular polarizers based on twisted helical vdW MoOCl2
heterostructures. Our findings display that vdW MoOCl2 provides a highly promising platform not only for
hyperbolic, but also for
chiral nanophotonic applications.
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All authors Artsruni Margaryan, Maksim Sargsyan, Meri Hayrapetyan, David Karakhanyan, Kostya S. Novoselov, Davit A. Ghazaryan
Materials Science
Disorder-mediated linear and nonlinear magnetotransport in the charge-density-wave material ${\rm Ta_2NiSe_7 }$
Xiaodong Sun, Jiabin Qiao, Yuanzhe Li et al. (+13 more)
We report disorder-mediated first-order linear and higher-order nonlinear (magneto-)transport of Ta$_2$NiSe$_7$ (TNS) in the charge-density-wave (CDW) regime. CDW transition temperature ($T_{CDW}$) and carrier density are proportional and inversely proportional to residual resistance ratio of samples, respectively. Such relation helps to understand the unique CDW order therein. High-$T_{CDW}$ TNS exhibits negative first-harmonic magnetoresistance (MR$^{1\omega}$) under a
magnetic field ($B$) parallel to the direction of alternating current ($I^{\omega}$), which may arise from the anomalous velocity induced by the Berry
curvature of three-dimensional topological bands near the
Fermi level. As $T_{CDW}$ drops, a positive-to-negative MR$^{1\omega}$ transition is observed with decreasing perpendicular $B$, which is likely due to the contribution of Zeeman effect on current pathways in the disordered system. Moreover, interestingly, the second-harmonic nonlinear signals are suppressed, while the third-harmonic signals are significant and sensitive to both $B$ and $T_{CDW}$. Such observations, together with scaling analysis, suggest the
quantum geometry quadrupole at play and the modulation of disorder on third-order nonlinearity. Our results pave an avenue for tailoring distinct-order magnetoresistive phases in disordered topological materials.
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All authors Xiaodong Sun, Jiabin Qiao, Yuanzhe Li, Wanli He, Jiali Chen, Jinjin Liu, Yuxiang Chen, Yuchen Ma, Meiling Jin, Jianlin Luo, Jie Chen, Wei Wu, Zhiwei Wang, Wei Jiang, Xiang Li, Yugui Yao
Strongly Correlated Electrons
Topological spin-up triplet excitonic condensation in two-dimensional electron-hole systems
Van-Nham Phan
We investigate topological
spin-up triplet excitonic condensation and its competition with other stabilities in a two-dimensional interacting electron-hole system taking into account Rashba
spin-orbit coupling and external
magnetic fields. Using an unrestricted Hartree-Fock approach, we self-consistently evaluate
spin-selective excitonic condensate order parameters and the Chern number. The ground state phase diagram in the dependence on
magnetic field and Coulomb interaction shows a
spin-up triplet excitonic condensate (EC) with a nonzero Chern number, emerging uniquely away from the topologically trivial singlet and
spin-down triplet EC regions. Strong
spin-polarized triplet excitonic fluctuations preceding the condensation are further revealed through the signatures of the dynamical excitonic susceptibility spectra. Our results establish a class of topological
quantum phases driven by excitonic coherence and suggest a realistic pathway to its realization in a distorted Janus monolayer of transition metal dichalcogenides or some twisted van der Waals
heterostructures.
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Soft Condensed Matter · Cross-listed from q-bio.BM
ATP-Independent Entropy-Driven dsRNA Unwinding by DDX3X Revealed by Coarse-Grained Simulations and Deep Learning
Kang Wang, Chun-Lai Ren and Yu-Qiang Ma
DEAD-box RNA helicases (DDXs) are traditionally known as ATP-dependent motors that unwind double-stranded RNA (dsRNA). Recent experiments, however, show that some DDXs promote dsRNA unwinding even in the absence of ATP, raising a fundamental question about the physical mechanism underlying ATP-independent strand separation. Here, we develop a minimal, physics-based coarse-grained RNA model and incorporate weak, specific interactions between DDX3X and dsRNA, revealing the inherently
stochastic nature of unwinding events. The unwinding process must overcome an energy barrier, but thermal fluctuations and
entropy gain provide a driving force for RNA remodeling. We identify that dsRNA separation proceeds through rare yet obligatory strand-displacing intermediates facilitated by DDX3X. By combining deep learning-assisted analysis, we further rank the contributions of different entropic components, revealing hydrogen bonding as the dominate factor, followed by base stacking and then the backbone conformation. These findings reveal a previously unrecognized physical mechanism for RNA duplex unwinding and offer an effective framework for studying RNA remodeling kinetics.
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Materials Science
Structural and Thermal Stability of B4C/Ru Multilayers with Carbon Barrier Layers
A.V. Bugaev, S.S. Sakhonenkov, A.U. Gaisin et al. (+3 more)
The chemical interaction between Mo and Ru layers in multilayer structures depending on the thickness ratio ($\Gamma$) was carried out using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and X-ray reflectometry (XRR). The results showed significant interaction of materials inside multilayer structures with the formation of ruthenium borides, with an increase in the B4C layer thickness (a decrease in the $\Gamma$ parameter) leading to the formation of ruthenium borides of different stoichiometry. The introduction of a carbon barrier layer at the Ru-on-B4C interface resulted in significant suppression of ruthenium boride formation. The thermal stability of the B4C/Ru system was also studied upon annealing at 400$^{\circ}$C for 1 hour before and after the introduction of the carbon barrier layer. It was shown that the introduction of a carbon barrier layer at the Ru-on-B4C interface increases the thermal stability of the system, which makes this system more suitable for use in optical systems exposed to long-term radiation. The obtained results are important for the development of highly efficient multilayer mirrors used in EUV lithography and X-ray optics.
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All authors A.V. Bugaev, S.S. Sakhonenkov, A.U. Gaisin, R.A. Shaposhnikov, V.N. Polkovnikov, E.O. Filatovaa
Materials Science
Halogen Chains with One-Dimensional Semi-Metallic Electronic Structure and Peierls Physics in Polymorphs of Na4X5 (X = I, Br, Cl) Compounds
Yuqing Yin, Nityasagar Jena, Florian Knoop et al. (+16 more)
Since the pioneering works of Peierls, one-dimensional materials have attracted great
attention. Still, the synthesis of truly monoatomic chains remains elusive. In this study, we explore a novel path of experimental synthesis of monoatomic one-dimensional chains by their chemical stabilization in ionic compounds. We demonstrate that in synthesized at high pressure sodium halides Na4X5 (X = I, Br, Cl) with hP18 Ga4Ti5-type structures, transfer of valence electrons from cations to anions leads to the formation of halogen chains connected with other atoms only by ionic interaction and having one-dimensional electronic structure. The Peierls physics in the systems is confirmed by theoretical calculations, newly synthesized incommensurately modulated i-hP18-Na4X5 (X = I, Br, Cl) compounds, as well as by the discovered hP36 phases of Na4Cl5 and Na4Br5.
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All authors Yuqing Yin, Nityasagar Jena, Florian Knoop, Gaston Garbarino, Ferenc Tasnádi, Florian Trybel, Sergei I. Simak, Mikhail I. Katsnelson, Alena Aslandukova, Andrey Aslandukov, Xiang Li, Anaëlle Antunes, Fariia Iasmin Akbar, Konstantin Glazyrin, Haixing Fang, James A. D. Ball, Natalia Dubrovinskaia, Leonid Dubrovinsky, Igor A. Abrikosov
Soft Condensed Matter
Forces at the scale of the cell
K. Vijay Kumar, Mandar M. Inamdar, Pramod A. Pullarkat et al. (+1 more)
The importance of molecular-scale forces in sculpting biological form and function has been acknowledged for more than a century. Accounting for forces in biology is a problem that lies at the intersection of soft condensed matter physics, statistical mechanics, and experimental methods, all adapted to a cellular context. This review surveys how forces arise within the
cell. We provide a summary of the relevant background in
cell biophysics, of soft-matter systems in and out of thermodynamic
equilibrium, and of various force measurement methods. These ideas are then deployed to describe how forces are generated, transmitted, and sensed in specific
cell-scale processes. We emphasize active matter descriptions, methodological tools that provide ways of incorporating non-
equilibrium effects in a systematic manner into conceptual as well as quantitative descriptions. Our examples include polymerization forces, the motion of molecular motors, the properties of the actomyosin cortex, the mechanics of
cell division, and shape changes in tissues. We suggest that a deeper understanding of
cell function will necessarily require integrating the action of
cell-scale physical forces with the assimilation and processing of information.
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All authors K. Vijay Kumar, Mandar M. Inamdar, Pramod A. Pullarkat, Gautam I. Menon
Materials Science
Ultrafast light-induced formation of a metastable hidden state in bismuth vanadate
Viktoria F. Kunzelmann, Verena Streibel, Philip Schwinghammer et al. (+24 more)
Bismuth vanadate (BiVO$_4$) is a key photocatalyst for
solar fuel applications, yet fundamental questions remain regarding the nature of photogenerated polaronic states and the
lattice dynamics that govern its light-to-chemical pathways. Here, we use femtosecond optical pump-X-ray probe measurements to track the photoinduced electronic and structural dynamics in BiVO$_4$ across multiple length and time scales. Transient X-ray absorption spectroscopy captures sub-picosecond electron localization within VO$_4$ tetrahedra, consistent with small polaron formation, whereas time-resolved X-ray diffraction reveals a slower, multi-picosecond
lattice reorganization into a hidden photoexcited state that is structurally distinct from both the monoclinic ground state and the high-temperature tetragonal phase. Supported by density functional theory, we show that hole-
lattice interactions dynamically reduce the ground state monoclinic distortion, stabilizing the hidden state. Our results demonstrate that electron- and hole-
lattice coupling jointly shape the excited state landscape, with implications for carrier transport, interfacial energetics, and light-to-chemical energy conversion pathways.
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All authors Viktoria F. Kunzelmann, Verena Streibel, Philip Schwinghammer, Philipp Kollenz, Burak Guzelturk, Franziska S. Hegner, Lissa Eyre, Frederico P. Delgado, Tsedenia A. Zewdie, Markus W. Heindl, Danyellen D. Monteiro Galindo, Daniel Sandner, Guanda Zhou, Elise Sirotti, Stanislav Bodnar, Yifeng Jiang, Yohei Uemura, Tobias Eklund, Frederico Lima, Xinchao Huang, Doriana Vinci, Fernando Ardana Lamas, Peter Zalden, Hristo Iglev, David A. Egger, Felix Deschler, Ian D. Sharp
Materials Science
A Transcorrelated Wave-Function Framework for Solids: An Application to Bulk and Defected Silicon
Kristoffer Simula, Johannes Hauskrecht, Evelin Martine Corvid Christlmaier et al. (+4 more)
Accurate wave-function descriptions of pristine and defected solids remain challenging due to the simultaneous presence of finite-size, basis-set, and correlation errors. While
embedding techniques alleviate finite-size effects and correlated wave-function approaches systematically improve correlation, basis-set incompleteness continues to limit practical accuracy. Here we present a study of transcorrelated (TC) many-body wave-function methods on properties of solid state systems. We augment the existing xTC theory to periodic systems, and establish an unified transcorrelated
embedding framework that integrates periodic TC theory with fragment-based correlated solvers. Using silicon as a test case, we validate the method against coupled-cluster, FCIQMC, and
diffusion Monte Carlo
benchmarks for bulk. Then we apply TC
embedding to calculation of formation energies of two silicon self-interstitials. The TC
Hamiltonian yields rapid basis convergence and quantitatively reliable defect formation energies at the triple-$\zeta$ level, substantially reducing the basis-set bottleneck for wave-function treatments of crystalline defects.
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All authors Kristoffer Simula, Johannes Hauskrecht, Evelin Martine Corvid Christlmaier, Pablo Lopez-Rios, Daniel Kats, Denis Usvyat, Ali Alavi
Superconductivity
Finite-Temperature $\textit{ab initio}$ Structural Optimization of the Bilayer Nickelate Superconductor La$_3$Ni$_2$O$_7$
Ryoma Asai, Ryotaro Arita, Takumi Chida et al. (+3 more)
We develop a first-principles framework for finite-temperature structural optimization that incorporates vibrational contributions to the free energy through anharmonic
phonon theory. We extend and further improve the efficiency of the recent approach, enabling its application to systems in which the size of the primitive
cell changes across structural phase transitions. Applying this framework to La$_3$Ni$_2$O$_7$, we establish its pressure-temperature phase diagram and find that the slope of the phase boundary between the high-
symmetry and low-
symmetry phases is negative, with a magnitude of approximately -60 K / GPa. The present results provide a theoretical foundation for discussing how changes in
crystal symmetry influence the emergence of superconductivity.
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All authors Ryoma Asai, Ryotaro Arita, Takumi Chida, Ryota Masuki, Kazuhiko Kuroki, Terumasa Tadano
Materials Science
Coalescence of multiple topological orders in quasi-one-dimensional bismuth halide chains
Jingyuan Zhong, Ming Yang, Wenxuan Zhao et al. (+14 more)
Topology is being widely adopted to understand and to categorize
quantum matter in modern physics. The nexus of
topology orders, which engenders distinct
quantum phases with benefits to both fundamental research and practical applications for future
quantum devices, can be driven by topological phase transition through modulating intrinsic or extrinsic ordering parameters. The conjoined
topology, however, is still elusive in experiments due to the lack of suitable material platforms. Here we use scanning tunneling microscopy, angle-resolved photoemission spectroscopy, and theoretical calculations to investigate the doping-driven band structure
evolution of a quasi-one-dimensional material system, bismuth halide, which contains rare multiple band inversions in two time-reversal-invariant momenta. According to the unique bulk-boundary correspondence in topological matter, we unveil a composite topological phase, the coexistence of a strong topological phase and a high-order topological phase, evoked by the band inversion associated with topological phase transition in this system. Moreover, we reveal multiple-stage topological phase transitions by varying the halide element ratio: from high-order
topology to weak
topology, the unusual dual
topology, and trivial/weak
topology subsequently. Our results not only realize an ideal material platform with composite
topology, but also provide an insightful pathway to establish abundant topological phases in the framework of band inversion theory.
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All authors Jingyuan Zhong, Ming Yang, Wenxuan Zhao, Kaiyi Zhai, Xuan Zhen, Lifu Zhang, Dan Mu, Yundan Liu, Zhijian Shi, Ningyan Cheng, Wei Zhou, Jianfeng Wang, Weichang Hao, Zhenpeng Hu, Jincheng Zhuang, Jinhu Lü, Yi Du
Mesoscale and Nanoscale Physics
Field manipulation of Weyl modes in an ideal Dirac semimetal
Jingyuan Zhong, Jianfeng Wang, Ming Yang et al. (+9 more)
The emergent Weyl modes with the broken time-reversal
symmetry or inversion
symmetry provide large Berry
curvature and chirality to carriers, offering the realistic platforms to explore
topology of electrons in three-dimensional systems. However, the reversal transition between different types of Weyl modes in a single material, which is of particular interest in the fundamental research in Weyl physics and potential application in spintronics, is scarcely achieved due to restriction of inborn
symmetry in
crystals. Here, by tuning the direction and strength of
magnetic field in an ideal Dirac semimetal, Bi4(Br0.27I0.73)4, we report the realization of multiple Weyl modes, including gapped Weyl mode, Weyl nodal ring, and coupled Weyl mode by the magnetoresistivity measurements and electronic structure calculations. Specifically, under a
magnetic field with broken mirror
symmetry, anomalous
Hall effect with step feature results from the large Berry
curvature for the gapped Weyl mode. A prominent negative magnetoresistivity is observed at low
magnetic field with preserved mirror
symmetry and disappears at high
magnetic field, which is correlated to the
chiral anomaly and its annihilation of Weyl nodal ring, respectively. Our findings reveal distinct Weyl modes under the intertwined
crystal symmetry and time-reversal breaking, laying the foundation of manipulating multiple Weyl modes in
chiral spintronic network.
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All authors Jingyuan Zhong, Jianfeng Wang, Ming Yang, Jie Liu, Zhizhen Ren, Anping Huang, Zhixiang Shi, Zengwei Zhu, Yan Shi, Weichang Hao, Jincheng Zhuang, Yi Du
Strongly Correlated Electrons · Cross-listed from hep-th
Haagerup Symmetry in $(E_8)_1$?
Jan Albert, Yamato Honda, Justin Kaidi et al. (+1 more)
We suggest that the
chiral $(\mathfrak{e}_8)_1$ theory – in many senses the simplest VOA – may have Haagerup
symmetry $\mathcal{H}_i$ for $i=1,2,3$. Likewise, we suggest that the non-
chiral $(E_8)_1$ WZW model may have $\mathcal{H}_i \times \mathcal{H}_i^\textrm{op}$
symmetry, and that gauging the diagonal
symmetry gives a $c=8$ theory with $\mathcal{Z}(\mathcal{H}_3)$
symmetry, which is the theory predicted in \cite{Evans:2010yr}. Along the way, we show that $(E_8)_1$ also has a $\mathrm{Fib} \times \mathrm{Fib}^\text{op}$
symmetry, and that gauging the diagonal
symmetry gives the $(G_2)_1 \times (F_4)_1$ WZW model, explaining the well-known conformal
embedding $(G_2)_1 \times (F_4)_1 \subset (E_8)_1$. Finally, we suggest a relation to theories with $\mathcal{H}_3$
symmetry at $c=2,6$, complimenting the discussion with new modular bootstrap results.
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All authors Jan Albert, Yamato Honda, Justin Kaidi, Yunqin Zheng
Quantum Gases
Direct Generation of an Array with 78400 Optical Tweezers Using a Single Metasurface
Yuqing Wang, Yuxuan Liao, Tao Zhang et al. (+9 more)
Scalability remains a major challenge in building practical fault-tolerant
quantum computers. Currently, the largest number of
qubits achieved across leading
quantum platforms ranges from hundreds to thousands. In atom arrays, scalability is primarily constrained by the capacity to generate large numbers of optical tweezers, and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond $\sim 10,000$ tweezers. Moreover, these methods require additional microscope objectives to focus the light into micrometer-sized spots, which further complicates system integration and scalability. Here, we demonstrate the experimental generation of an optical tweezer array containing $280\times 280$ spots using a metasurface, nearly an order of magnitude more than most existing systems. The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light, enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope. This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available
laser power. Furthermore, the array shows excellent intensity uniformity exceeding $90\%$, making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than $10,000$ atoms in the near future.
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All authors Yuqing Wang, Yuxuan Liao, Tao Zhang, Ye Tian, Yujia Wu, Wenjun Zhang, Wei Zhang, Yidong Huang, Hui Zhai, Wenlan Chen, Xue Feng, Zhongchi Zhang
Strongly Correlated Electrons
Leandro M. Chinellato, Oleg A. Starykh and Cristian D. Batista
We introduce a nonperturbative framework for quantizing
chiral solitons in interacting
quantum spin chains. This approach provides a direct
lattice extension of the well-established $S$-duality between the sine-Gordon and Thirring models, thereby bridging the gap between continuum dualities and their
lattice counterparts. By constructing the
quantum chiral-
soliton operators explicitly, we show how their unconventional dynamics appear in the excitation spectrum and correlation functions across the full Brillouin zone. A key result is that the dominant
soliton tunneling amplitude alternates in sign, $\operatorname{sgn}(t_{1+}) = (-1)^{2S+1}$, sharply distinguishing half-odd-integer from integer
spin chains. We further identify characteristic signatures of these
chiral excitations in the dynamical
spin structure factor, demonstrating their visibility in inelastic
neutron scattering. Our results open a route to experimentally probing nonperturbative features of dual
quantum field theories in condensed-matter settings.
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Statistical Mechanics
Nonreciprocal dynamics with weak noise: aperiodic "Escher cycles" and their quasipotential landscape
Janik Schüttler, Robert L. Jack and Michael E. Cates
We present an explicit construction of the Freidlin-Wentzell quasipotential of a
stochastic system with two degrees of freedom and nonreciprocal interactions. This model undergoes noise-induced transitions between four metastable attractors, forming recurrent but aperiodic “Escher cycles,” similar to the cyclic nucleation dynamics observed in the nonreciprocal Ising model. We calculate the quasipotential analytically to first order in nonreciprocality. We characterise it along a one-dimensional reaction coordinate that connects the attractors, and we also obtain the full two-dimensional landscape, at leading order in perturbation theory. The resulting landscapes feature flat regions and extended plateaus, together with non-differentiable switching lines. These singular structures arise from two
geometric mechanisms: the handover of dominance between competing transition paths, and the competition between basins of attraction. The system provides a rare case where the geometry of nonequilibrium rare events can be fully resolved, and a simple analytically tractable example of a quasipotential in more than one coordinate that captures a rich set of nonequilibrium features.
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Other Condensed Matter
Highly anisotropic nonrelativistic charge-to-spin conversion in altermagnets
Mingbo Dou, Xu Chen, Zhiguo Liu et al. (+3 more)
The charge-to-
spin conversion provides an efficient way to manipulate the magnetization by electrical means. In this work, we report on a study on the anisotropic nonrelativistic charge-to-
spin conversion response to the current direction in altermagnets. We prove that the
spin conductivity dictating the charge-to-
spin conversion is equivalent to the
spin-polarized conductivity difference in the nonrelativistic limit. Based on the general
spin-group analysis, we derive analytical expressions for the anisotropic conversion ratio and identify its maximum value. We then exemplify those phenomena in representative altermagnets based on the density functional theory calculations. The highly anisotropic charge-to-
spin conversion efficiency, varying from zero to several tens of percent, was demonstrated. Our work shines more light on the exploration of the nonrelativistic generation of
spin currents in altermagnets.
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All authors Mingbo Dou, Xu Chen, Zhiguo Liu, Yu Sui, Xianjie Wang, L. L. Tao
Mesoscale and Nanoscale Physics
Device/circuit simulations of silicon spin qubits based on a gate-all-around transistor
Tetsufumi Tanamoto and Keiji Ono
We theoretically investigated the readout process of a
spin–
qubit structure based on a gate-all-around (GAA) transistor. Our study focuses on a logical
qubit composed of two physical
qubits. Different
spin configurations result in different charge distributions, which subsequently influence the electrostatic effects on the GAA transistor. Consequently, the current flowing through the GAA transistor depends on the
qubit's state. We calculated the current-voltage characteristics of the three-dimensional configurations of the
qubit and GAA structures, using technology computer-aided design (TCAD) simulations. Moreover, we performed
circuit simulations using the Simulation Program with Integrated
Circuit Emphasis (SPICE) to investigate whether a readout
circuit made from complementary metal–
oxide semiconductor (CMOS) transistors can amplify the weak signals generated by the
qubits. Our findings indicate that, by dynamically controlling the applied voltage within a properly designed
circuit, the readout can be detected effectively based on a conventional sense amplifier.
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Materials Science
Enhancing Hole Mobility in Monolayer $WSe_{2}$ p-FETs via Process-Induced Compression
He Lin Zhao, Sheikh Mohd Ta-Seen Afrid, Dongyoung Yoon et al. (+7 more)
Understanding the interactions between strain, interfacial mechanics, and electrical performance is critical for designing beyond silicon electronics based on hetero-integrated 2D materials. Through combined experiment and simulation, we demonstrated and analyzed the enhancement of hole mobility in p-type monolayer $WSe_{2}$ field effect transistors (FETs) under biaxial compression. We tracked FET performance versus strain by incrementing compressive strain to $WSe_{2}$ channels via sequential AlOx deposition and performing intermediate photoluminescence and transport measurements. The hole mobility factor increased at a rate of 340 $\pm$ 95 %/%$\epsilon$, and the on-current factor increased at a rate of 460 $\pm$ 340 %/%$\epsilon$. Simulation revealed that the enhancement under compression arises primarily from a reduction in inter-valley scattering between the $\Gamma$–K valence bands, and the rate is robust against variations in carrier density,
impurity density, or dielectric environment. These findings show that compressive strain is a powerful technique for enhancing performance in 2D p-FETs and that it is multiplicative with defect and doping engineering.
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All authors He Lin Zhao, Sheikh Mohd Ta-Seen Afrid, Dongyoung Yoon, Zachary Martin, Zakaria Islam, Sihan Chen, Yue Zhang, Pinshane Y. Huang, Shaloo Rakheja, Arend M. van der Zande
Superconductivity
Self-consistent solution of Eliashberg equations for metal hydride superconductors
Tomas J. Escamilla and Chumin Wang
In recent years, the quest for high critical-temperature
superconductors has increasingly focused on metal and molecular hydrides, which have demonstrated potential for superconductivity at or near room temperature under extremely high pressures. Such hydrides were first proposed by N. W. Ashcroft in 1968, because hydrogen-rich materials possess elevated vibrational frequencies due to the low atomic mass of hydrogen. This article presents a self-consistent solution to the Eliashberg equations for analysing superconductivity in hydrides, contrasting with the commonly used McMillan-Allen-Dynes parameterized formula. We also analyse effects of the electron-
phonon spectral function and the broadening parameters arising from
phonon lifetime and sample imperfections on the superconducting critical temperature. Finally, both theoretical approaches are applied to a typical metal hydride
superconductor, and the reliability of self-consistent solutions is validated against the experimentally measured critical temperature.
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