CMP Journal 2025-02-10
Statistics
Nature Materials: 2
Nature Nanotechnology: 3
Nature Physics: 1
Nature Reviews Materials: 1
Physical Review Letters: 14
Physical Review X: 1
arXiv: 53
Nature Materials
A quantum dot in germanium proximitized by a superconductor
Original Paper | Electronic properties and materials | 2025-02-09 19:00 EST
Lazar Lakic, William I. L. Lawrie, David van Driel, Lucas E. A. Stehouwer, Yao Su, Menno Veldhorst, Giordano Scappucci, Ferdinand Kuemmeth, Anasua Chatterjee
As one of the few group IV materials with the potential to host superconductor-semiconductor hybrid devices, planar germanium hosting proximitized quantum dots is a compelling platform to achieve and combine topological superconductivity with existing and new qubit modalities. We demonstrate a quantum dot in a Ge/SiGe heterostructure proximitized by a platinum germanosilicide (PtSiGe) superconducting lead, forming a superconducting lead-quantum dot-superconducting lead junction. We show tunability of the coupling strength between the quantum dot and the superconducting lead, and gate control of the ratio of charging energy and the induced gap, and we tune the ground state of the system between even and odd parity. Furthermore, we characterize critical magnetic field strengths, finding a critical out-of-plane field of 0.90 ± 0.04 T. Finally, we explore sub-gap spin splitting, observing rich physics in the resulting spectra, that we model using a zero-bandwidth model in the Yu-Shiba-Rusinov limit. Our findings open up the physics of alternative spin and superconducting qubits, and the physics of Josephson junction arrays, in germanium.
Electronic properties and materials, Quantum dots, Quantum information, Superconducting devices, Superconducting properties and materials
General approach for synthesizing hexagonal diamond by heating post-graphite phases
Original Paper | Mechanical properties | 2025-02-09 19:00 EST
Desi Chen, Guwen Chen, Long Lv, Jiajun Dong, Yuchen Shang, Xuyuan Hou, Yan Wang, Jianqi Shang, Saisai Wang, Yankun Yin, Ran Liu, Wei Zhang, Zhou Jiang, Yan He, Bingchen He, Chengwen Mao, Shengcai Zhu, Bertil Sundqvist, Bingbing Liu, Mingguang Yao
Natural and synthetic diamonds mostly have a cubic lattice, whereas a rare hexagonal structure--known as hexagonal diamond (HD)--has been largely unexplored due to the low purity and minuscule size of most samples obtained. The synthesis of HD remains a challenge and even its existence remains controversial. Here we report the synthesis of well-crystallized, nearly pure HD by heating highly compressed graphite, which is applicable to both bulk and nanosized graphitic precursors. Experiments and theoretical analyses show that the formation of a post-graphite phase within compressed graphite and temperature gradients promote HD growth. Using this approach, a millimetre-sized, highly oriented HD block comprising stacked single-crystal-like HD nanolayers is obtained. This HD exhibits high thermal stability up to 1,100 °C and a very high hardness of 155 GPa. Our findings offer valuable insights regarding the graphite-to-diamond conversion under elevated pressure and temperature, providing opportunities for the fabrication and applications of this unique material.
Mechanical properties, Structure of solids and liquids
Nature Nanotechnology
Customizable virus-like particles deliver CRISPR-Cas9 ribonucleoprotein for effective ocular neovascular and Huntington's disease gene therapy
Original Paper | Drug delivery | 2025-02-09 19:00 EST
Sikai Ling, Xue Zhang, Yao Dai, Zhuofan Jiang, Xujiao Zhou, Sicong Lu, Xiaoqing Qian, Jianping Liu, Niklas Selfjord, Tugce Munise Satir, Anders Lundin, Julia Liz Touza, Mike Firth, Natalie Van Zuydam, Bilada Bilican, Pinar Akcakaya, Jiaxu Hong, Yujia Cai
In vivo CRISPR gene editing holds enormous potential for various diseases. Ideally, CRISPR delivery should be cell type-specific and time-restricted for optimal efficacy and safety, but customizable methods are lacking. Here we develop a cell-tropism programmable CRISPR-Cas9 ribonucleoprotein delivery system (RIDE) based on virus-like particles. The efficiency of RIDE was comparable to that of adeno-associated virus and lentiviral vectors and higher than lipid nanoparticles. RIDE could be readily reprogrammed to target dendritic cells, T cells and neurons, and significantly ameliorated the disease symptoms in both ocular neovascular and Huntington's disease models via cell-specific gene editing. In addition, RIDE could efficiently edit the huntingtin gene in patients' induced pluripotent stem cell-derived neurons and was tolerated in non-human primates. This study is expected to facilitate the development of in vivo CRISPR therapeutics.
Drug delivery, Nanoparticles
Nanopore discrimination of rare earth elements
Original Paper | Nanopores | 2025-02-09 19:00 EST
Wen Sun, Yunqi Xiao, Kefan Wang, Shanyu Zhang, Lang Yao, Tian Li, Bingxiao Cheng, Panke Zhang, Shuo Huang
Rare earth elements (REEs), including scandium, yttrium and lanthanides, are strategic resources with unique electric, luminescent and magnetic properties. However, owing to their highly similar physiochemical properties, the identification and separation of all REEs are challenging. Here a Mycobacterium smegmatis porin A nanopore is engineered to contain a nitrilotriacetic acid ligand at its pore constriction. By the further introduction of a secondary ligand Nα,Nα-bis(carboxymethyl)-L-lysine hydrate (ANTA), a dual-ligand sensing strategy was established. A unique property of this strategy is that a variety of REE(III) ions report characteristic blockage features containing three-level transitions, which are critical in discriminating different REE(III)s. The nanopore events of REE(III)s also demonstrate a clear periodicity, suggesting the observation of the lanthanide contraction effect at a single-molecule regime. Assisted by machine learning, all 16 naturally occurring REE(III)s have been identified by the nanopore with high accuracy. This sensing strategy is further applied in analysing bastnaesite samples, suggesting its potential use in geological exploration.
Nanopores, Sensors
Spin-valley protected Kramers pair in bilayer graphene
Original Paper | Electronic properties and devices | 2025-02-09 19:00 EST
Artem O. Denisov, Veronika Reckova, Solenn Cances, Max J. Ruckriegel, Michele Masseroni, Christoph Adam, Chuyao Tong, Jonas D. Gerber, Wei Wister Huang, Kenji Watanabe, Takashi Taniguchi, Thomas Ihn, Klaus Ensslin, Hadrien Duprez
The intrinsic valley degree of freedom makes bilayer graphene (BLG) a unique platform for semiconductor qubits. The single-carrier quantum dot (QD) ground state exhibits a twofold degeneracy, where the two states that constitute a Kramers pair have opposite spin and valley quantum numbers. Because of the valley-dependent Berry curvature, an out-of-plane magnetic field breaks the time-reversal symmetry of this ground state and a qubit can be encoded in the spin-valley subspace. The Kramers states are protected against known spin- and valley-mixing mechanisms because mixing requires a simultaneous change of the two quantum numbers. Here, we fabricate a tunable QD device in Bernal BLG and measure a spin-valley relaxation time for the Kramers states of 38 s at 30 mK, which is two orders of magnitude longer than the 0.4 s measured for purely spin-blocked states. We also show that the intrinsic Kane-Mele spin-orbit splitting enables a Kramers doublet single-shot readout even at zero magnetic field with a fidelity above 99%. If these long-lived Kramers states also possess long coherence times and can be effectively manipulated, electrostatically defined QDs in BLG may serve as long-lived semiconductor qubits, extending beyond the spin qubit paradigm.
Electronic properties and devices, Electronic properties and materials, Quantum dots, Qubits, Two-dimensional materials
Nature Physics
Nematicity and orbital depairing in superconducting Bernal bilayer graphene
Original Paper | Electronic properties and devices | 2025-02-09 19:00 EST
Ludwig Holleis, Caitlin L. Patterson, Yiran Zhang, Yaar Vituri, Heun Mo Yoo, Haoxin Zhou, Takashi Taniguchi, Kenji Watanabe, Erez Berg, Stevan Nadj-Perge, Andrea F. Young
Superconductivity is a common feature of graphite allotropes, having been observed in Bernal bilayers, rhombohedral trilayers and a wide variety of angle-misaligned multilayers. Despite notable differences in the electronic structure of these systems, supporting the graphite on a WSe2 substrate has been consistently observed to expand the range of the superconductivity in terms of carrier density and temperature. Here we report the observation of two distinct superconducting states in Bernal bilayer graphene with strong proximity-induced Ising spin-orbit coupling. Our quantum oscillation measurements show that, although the normal state of the first superconducting phase is consistent with the single-particle band structure, the second emerges from a nematic normal state with broken rotational symmetry. Both superconductors are robust to in-plane magnetic fields, but neither reach fields expected for spin-valley-locked Ising superconductors. The Fermi surface geometry of the first superconducting phase suggests that the superconductivity is limited by orbital depairing arising from the imperfect layer polarization of the electron wavefunctions. Finally, an analysis of transport and thermodynamic compressibility measurements in the second superconducting phase shows that the proximity to isospin phase boundaries, observed in other rhombohedral graphene allotropes, is probably coincidental, thus constraining theories of the pairing mechanisms in these systems.
Electronic properties and devices, Superconducting properties and materials
Nature Reviews Materials
Visible-to-THz near-field nanoscopy
Review Paper | Condensed-matter physics | 2025-02-09 19:00 EST
Rainer Hillenbrand, Yohannes Abate, Mengkun Liu, Xinzhong Chen, D. N. Basov
Optical microscopy has a key role in research, development and quality control across a wide range of scientific, technological and medical fields. However, diffraction limits the spatial resolution of conventional optical instruments to about half the illumination wavelength. A technique that surpasses the diffraction limit in the wide spectral range between visible and terahertz frequencies is scattering-type scanning near-field optical microscopy (s-SNOM). The basis of s-SNOM is an atomic force microscope in which the tip is illuminated with light from the visible to the terahertz spectral range. By recording the elastically tip-scattered light while scanning the sample below the tip, s-SNOM yields near-field optical images with a remarkable resolution of 10 nm, simultaneously with the standard atomic force microscopic topography image. This resolution is independent of the illumination wavelength, rendering s-SNOM a versatile nanoimaging and nanospectroscopy technique for fundamental and applied studies of materials, structures and phenomena. This Review presents an overview of the fundamental principles governing the measurement and interpretation of near-field contrasts and discusses key applications of s-SNOM. We also showcase emerging developments that enable s-SNOM to operate under various environmental conditions, including cryogenic temperatures, electric and magnetic fields, electrical currents, strain and liquid environments. All these recent developments broaden the applicability of s-SNOMs for exploring fundamental solid-state and quantum phenomena, biological matter, catalytic reactions and more.
Condensed-matter physics, Infrared spectroscopy, Optical materials and structures, Optical spectroscopy
Physical Review Letters
Multipath and Multiparticle Tests of Complex versus Hypercomplex Quantum Theory
Research article | Optical tests of quantum theory | 2025-02-10 05:00 EST
Ece İpek Saruhan, Joachim von Zanthier, and Marc-Oliver Pleinert
The axioms of quantum mechanics provide limited information regarding the structure of the Hilbert space, such as the underlying number system. The latter is generally regarded as complex, but generalizations of complex numbers, so-called hypercomplex numbers, cannot be ruled out in theory. Therefore, specialized experiments to test for hypercomplex quantum mechanics are needed. To date, experimental tests are limited to single-particle interference exploiting a closed phase relation in a three-path interferometer called the Peres test. The latter distinguishes complex quantum mechanics from quaternionic quantum mechanics. Here, we propose a general matrix formalism putting the Peres test on a solid mathematical ground. On this basis, we introduce multipath and multiparticle interference tests, which provide a direct probe for any dimension of the number system of quantum mechanics.
Phys. Rev. Lett. 134, 060201 (2025)
Optical tests of quantum theory, Quantum foundations, Quantum optics
Floquet Expansion by Counting Pump Photons
Research article | Quantum formalism | 2025-02-10 05:00 EST
Kilian Seibold, Orjan Ameye, and Oded Zilberberg
Periodically driven systems engender a rich competition between the timescales of the drives and those of the system, leading to a limited ability to describe the system in full. We present a framework for the description of interacting bosonic driven systems via a Floquet expansion on top of a quantization that ''counts'' the drive photons, and provide compelling arguments for the superior performance of our method relative to standard Floquet approaches. Crucially, our approach extends beyond the rotating wave approximation and addresses the long-standing issue of mismatch between the quantum Floquet formalism and its classical counterpart. We, furthermore, pinpoint key corrections to the positions of multiphoton resonances, which are commonly used in the calibration and operation of qubit architectures.
Phys. Rev. Lett. 134, 060401 (2025)
Quantum formalism, Floquet systems, Rotating wave approximation
Measurement of the Branching Fraction Ratios \(R({D}^{+})\) and \(R({D}^{\ast+})\) Using Muonic $$ Decays
Research article | Particle decays | 2025-02-10 05:00 EST
R. Aaij et al. (LHCb Collaboration)
The branching fraction ratios of \({\overline{B}}^{0}\rightarrow {D}^{+}{\tau }^{- }{\overline{\nu }}_{\tau }\) and \({\overline{B}}^{0}\rightarrow {D}^{\ast+}{\tau }^{- }{\overline{\nu }}_{\tau }\) decays are measured with respect to their muonic counterparts, using a data sample corresponding to an integrated luminosity of \(2.0\text{ }\text{ }{\mathrm{fb}}^{- 1}\) collected by the LHCb experiment in proton-proton collisions at \(\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}\). The reconstructed final states are formed by combining \({D}^{+}\) mesons with \({\tau }^{- }\rightarrow {\mu }^{- }{\overline{\nu }}_{\mu }{\nu }_{\tau }\) candidates, where the \({D}^{+}\) is reconstructed via the \({D}^{+}\rightarrow {K}^{- }{\pi }^{+}{\pi }^{+}\) decay. The results are \(R({D}^{+})=0.249\pm{}0.043\pm{}0.047\), \(R({D}^{\ast+})=0.402\pm{}0.081\pm{}0.085\), where the first uncertainties are statistical and the second systematic. The two measurements have a correlation coefficient of \(- 0.39\) and are compatible with the standard model.
Phys. Rev. Lett. 134, 061801 (2025)
Particle decays, Bottom mesons, Muons, Tau leptons, Flavor symmetries, Hadron colliders, Particle data analysis, Precision measurements
Factorization Restoration through Glauber Gluons
Research article | Effective field theory | 2025-02-10 05:00 EST
Thomas Becher, Patrick Hager, Sebastian Jaskiewicz, Matthias Neubert, and Dominik Schwienbacher
We analyze the low-energy dynamics of gap-between-jets cross sections at hadron colliders, for which phase factors in the hard amplitudes spoil collinear cancellations and lead to double (''super-leading'') logarithmic behavior. Based on a method-of-regions analysis, we identify three-loop contributions from perturbative active-active Glauber-gluon exchanges with the right structure to render the cross section consistent with PDF factorization below the gap veto scale. The Glauber contributions we identify are unambiguously defined without regulators beyond dimensional regularization.
Phys. Rev. Lett. 134, 061901 (2025)
Effective field theory, Perturbation theory, Quantum chromodynamics, Renormalization, Resummation methods
Convergent Close-Coupling Approach to Electron Impact Dissociation of the Polyatomic Molecule \({\mathrm{H}}_{3}^{+}\) and Its Isotopologues
Research article | Atomic & molecular collisions | 2025-02-10 05:00 EST
Reese K. Horton, Michael V. Pak, Igor Bray, and Dmitry V. Fursa
Cross sections for electron impact dissociative excitation and ionization in scattering on vibrationally excited levels of the ground electronic state of \({\mathrm{H}}_{3}^{+}\) and its isotopologues are reported in the energy range of 8 to 1000 eV. Calculations have been performed using a newly developed version of the molecular convergent close-coupling code. Cross sections for total dissociative excitation, ionization yielding atomic fragments such as \({\mathrm{D}}^{+}\), and the total inelastic cross section are presented. Good agreement with available experiments has been demonstrated.
Phys. Rev. Lett. 134, 063001 (2025)
Atomic & molecular collisions, Electron & positron scattering, Electronic excitation & ionization, Electronic transitions, Ionized molecules
Anderson Transition at Complex Energies in One-Dimensional Parity-Time-Symmetric Disordered Systems
Research article | Anderson localization | 2025-02-10 05:00 EST
Wei Wang, Xulong Wang, and Guancong Ma
One-dimensional disordered rings with chiral hopping can host Anderson localized modes which exhibit complex energies, a phenomenon previously associated exclusively with extended modes.
Phys. Rev. Lett. 134, 066301 (2025)
Anderson localization, Classical mechanics, Non-Hermitian systems, Random & disordered media
Multiple Chern Bands in Twisted \({\mathrm{MoTe}}_{2}\) and Possible Non-Abelian States
Research article | Exact diagonalization | 2025-02-10 05:00 EST
Cheng Xu, Ning Mao, Tiansheng Zeng, and Yang Zhang
We investigate the moir'e band structures and a possible even-denominator fractional quantum Hall state in small angle twisted bilayer \({\mathrm{MoTe}}_{2}\), using combined large-scale local basis density functional theory calculation and continuum model exact diagonalization. Via large-scale first-principles calculations at \(\theta =1.89^\circ{}\), we find a sequence of \(C=1\) (Chern number in the K valley) moir'e Chern bands in analogy to Landau levels. By constructing the continuum model with multiple Chern bands, we undertake a band-projected exact diagonalization using an unscreened Coulomb repulsion to identify possible non-Abelian states near twist angle \(\theta =1.89^\circ{}\) at the half filling of second moir'e band.
Phys. Rev. Lett. 134, 066601 (2025)
Exact diagonalization, First-principles calculations
Topological Exciton Density Wave in Monolayer \({\mathrm{WSe}}_{2}\)
Research article | Excited-state quantum phase transitions | 2025-02-10 05:00 EST
Shan Dong, Yingda Chen, Hongwei Qu, Wen-Kai Lou, and Kai Chang
Based on the first-principles calculations coupled with the Bethe-Salpeter equation, the topological exciton density wave is investigated in two-dimensional monolayer \({\mathrm{WSe}}_{2}\). We find that the topological excitonic insulator phase can exist in monolayer \({\mathrm{WSe}}_{2}\), and it is robust against in-plane strain. In this system, the energy minimum of exciton bands is shifted to a finite in-plane momentum, forming a Fulde-Ferrell-Larkin-Ovchinnikov-like state. Using the Gross-Pitaevskii equations, stripe-patterned exciton density waves with a nonzero velocity emerge in monolayer \({\mathrm{WSe}}_{2}\). Our findings pave a new way for exploring the interplay between electron correlation and nontrivial topology.
Phys. Rev. Lett. 134, 066602 (2025)
Excited-state quantum phase transitions, Excitons, Topological insulators, Bose-Einstein condensates, Transition metal dichalcogenides, Bethe-Salpeter equation, GW method, k dot p method
Observation of Temperature-Independent Anomalous Hall Effect in Thin Bismuth from Near Absolute Zero to 300 K Temperature
Research article | Anomalous Hall effect | 2025-02-10 05:00 EST
Oulin Yu, F. Boivin, A. Silberztein, and G. Gervais
We report our discovery of a temperature-independent anomalous Hall effect (AHE) from 15 mK to 300 K temperature occurring in a pure bismuth transport device whose average thickness is 68 nm. This surprising behavior is accompanied with an expected temperature-dependent longitudinal resistance consistent with semimetallic bismuth. However, it surprisingly showed no hint of a magnetoresistance for magnetic fields between \(\pm{}30\text{ }\text{ }\mathrm{T}\). Even though bismuth is a diamagnetic material that a priori does not break time-reversal symmetry, our analysis of the reconstructed conductivities points toward the AHE to be of the intrinsic type that does not emanate from magnetic impurities. Finally, as pure bismuth has been shown numerically to host a Berry curvature at its surface that breaks inversion symmetry, we propose it as a possible explanation for the temperature-independent AHE observed here.
Phys. Rev. Lett. 134, 066603 (2025)
Anomalous Hall effect, Berry curvature, Electrical conductivity, Hall effect, 2-dimensional systems, Elemental materials
Optical Absorption in Indirect Semiconductor to Semimetal \({\mathrm{PtSe}}_{2}\) Arises from Direct Transitions
Research article | Excitons | 2025-02-10 05:00 EST
Marin Tharrault, Sabrine Ayari, Mehdi Arfaoui, Eva Desgué, Romaric Le Goff, Pascal Morfin, José Palomo, Michael Rosticher, Sihem Jaziri, Bernard Plaçais, Pierre Legagneux, Francesca Carosella, Christophe Voisin, Robson Ferreira, and Emmanuel Baudin
\({\mathrm{PtSe}}_{2}\) is a van der Waals material transitioning from an indirect band gap semiconductor to a semimetal with increasing thickness. Its absorption threshold has been conjectured to originate from interband indirect transitions. By quantitative comparison between broadband (0.8--3.0 eV) optical absorption of high-quality exfoliated crystals and DFT ab initio simulations, we prove instead that the optical absorption arises only from direct transitions. This understanding allows us to shed light on the semiconductor-to-semimetal transition in an emblematic strongly thickness-dependent 2D material, and to explore the effect of stacking and excitons on the optical absorption.
Phys. Rev. Lett. 134, 066901 (2025)
Excitons, Optical & microwave phenomena, Transition metal dichalcogenides, Confocal imaging, Density functional theory, GW method, Raman spectroscopy
Tunable Spatiotemporal Orders in Driven Insulators
Research article | Charge density waves | 2025-02-10 05:00 EST
Daniel Kaplan, Pavel A. Volkov, Ahana Chakraborty, Zekun Zhuang, and Premala Chandra
A new method can use light to generate incommensurate order, spatial as well as temporal, in insulators of any symmetry.
Phys. Rev. Lett. 134, 066902 (2025)
Charge density waves, Dzyaloshinskii-Moriya interaction, Light-matter interaction, Parametric resonance, Phonons, Time crystals, Ferroelectrics, Superlattices
Distinct Optical Excitation Mechanisms of a Coherent Magnon in a van der Waals Antiferromagnet
Research article | Light-induced magnetic effects | 2025-02-10 05:00 EST
Clifford J. Allington, Carina A. Belvin, Urban F. P. Seifert, Mengxing Ye, Tommy Tai, Edoardo Baldini, Suhan Son, Junghyun Kim, Jaena Park, Je-Geun Park, Leon Balents, and Nuh Gedik
The control of antiferromagnets with ultrashort optical pulses has emerged as a prominent field of research. Tailored laser excitation can launch coherent spin waves at terahertz frequencies, yet a comprehensive description of their generation mechanisms is still lacking despite extensive efforts. Using terahertz emission spectroscopy, we investigate the generation of a coherent magnon mode in the van der Waals antiferromagnet \({\mathrm{NiPS}}_{3}\) under a range of photoexcitation conditions. By tuning the pump photon energy from transparency to resonant with a \(d\text{- }d\) transition, we reveal a striking change in the coherent magnon's dependence on the pump polarization, indicating two distinct excitation mechanisms. Our findings provide a strategy for the manipulation of magnetic modes via photoexcitation around subgap electronic states.
Phys. Rev. Lett. 134, 066903 (2025)
Light-induced magnetic effects, Magneto-optics, Magnons, Spin dynamics, Ultrafast magnetic effects
Multiplet Supercurrents in a Josephson Circuit
Research article | Cooper pairs | 2025-02-10 05:00 EST
Ethan G. Arnault, John Chiles, Trevyn F. Q. Larson, Chun-Chia Chen, Lingfei Zhao, Kenji Watanabe, Takashi Taniguchi, François Amet, and Gleb Finkelstein
Multiplet supercurrents mediated by two Cooper pairs have been observed in graphene-based Josephson junctions.
Phys. Rev. Lett. 134, 067001 (2025)
Cooper pairs, Josephson effect, Superconducting RF, Graphene, Josephson junctions
Erratum: Noninductively Driven Tokamak Plasmas at Near-Unity Toroidal Beta [Phys. Rev. Lett. 119, 035001 (2017)]
Magnetic confinement fusion | 2025-02-10 05:00 EST
D. J. Schlossberg, G. M. Bodner, M. W. Bongard, M. G. Burke, R. J. Fonck, J. M. Perry, and J. A. Reusch
Phys. Rev. Lett. 134, 069901 (2025)
Magnetic confinement fusion, Nuclear fusion, Plasma fusion, Laboratory plasma, Magnetically confined plasmas, Tokamaks, Time-resolved light scattering spectroscopy
Physical Review X
Multiscale Physics of Atomic Nuclei from First Principles
Research article | Collective levels | 2025-02-10 05:00 EST
Z. H. Sun, A. Ekström, C. Forssén, G. Hagen, G. R. Jansen, and T. Papenbrock
A new computational method could help scientists understand the shapes of deformed nuclei from first principles.
Phys. Rev. X 15, 011028 (2025)
Collective levels, Electromagnetic transitions, Nuclear many-body theory, Bayesian methods, Quantum chemistry methods
arXiv
Nano-size fragmentation of Tantalum in Copper composite using additive manufacturing
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Rakesh Das, Pawan Kumar Dubey, Raphael Benjamim de Oliveira, Douglas S. Galvao, Indranil Manna, Sameehan S. Joshi, Peter Samora Owuor, Leonardo D. Machado, Nirmal Kumar Katiyar, Suman Chakraborty, Chandra Sekhar Tiwary
The biggest challenge in manufacturing an immiscible system is phase segregation and non-uniformity inside the composite matrix. Additive manufacturing has the potential to overcome these difficulties due to the high cooling rate achieved during the process. Here we have developed immiscible Copper-based composites reinforced with Tantalum, which were fabricated using the powder bed fusion melting (PBF-M) technique. The distinct advantage of utilizing Tantalum in this process resides in its high melting point, allowing it to remain in particle form within the composite and contribute to its mechanical and surface/wear properties. The PBF-M results in the in situ fragmentation of micron-size Tantalum particles into nanoparticle form through a surface roughening process during laser interaction, enhancing its mechanical and wear properties. The microstructural evolution of Cu-Ta composites is explained through multiscale numerical modeling. The enhanced yield strength and the dynamics of the Ta particles were corroborated by molecular dynamics simulations. The maximum yield strength is exhibited by Cu-5wt%Ta of 80 MPa. Addition of Ta also have significant improvement in wear properties of composites. The current results can be exploited to develop complex shape, high energy efficient copper-based composites.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Vibrationally Assisted Exciton Transfer in Open Quantum Systems with Long-Range Interactions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Diego Fallas Padilla, Visal So, Abhishek Menon, Roman Zhuravel, Han Pu, Guido Pagano
The interplay between coherence and system-environment interactions is at the basis of a wide range of phenomena, from quantum information processing to charge and energy transfer in molecular systems, biomolecules, and photochemical materials. In this work, we use a Frenkel-exciton model with long-range interacting qubits coupled to a damped collective bosonic mode to investigate vibrationally assisted transfer processes in donor-acceptor systems featuring internal substructures analogous to light-harvesting complexes. We find that certain delocalized excitonic states maximize the transfer rate and that the entanglement is preserved during the dissipative transfer over a wide range of parameters. We investigate the transfer reduction by static disorder and by finite temperature and study how transfer efficiency scales as a function of the number of dimerized monomers and the component number of each monomer, finding which excitonic states lead to optimal transfer. Finally, we provide a realistic experimental setting to realize this model in analog trapped-ion quantum simulators. Analog quantum simulation of systems comprising many and increasingly complex monomers could offer valuable insights into the design of light-harvesting materials, particularly in the non-perturbative intermediate parameter regime examined in this study, where classical simulation methods are resource-intensive.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas), Chemical Physics (physics.chem-ph), Quantum Physics (quant-ph)
16 pages, 6 figures, Appendices included
On the extension of the concept of rheological connections to a finite deformation framework using multiple natural configurations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
The constitutive behaviors of materials are often modeled using a network of different rheological elements. These rheological models are mostly developed within a one-dimensional small strain framework. One of the key impediments of extending these models to a three-dimensional finite deformation setting is to determine how the different types of connections, i.e., a series and a parallel connection, are incorporated into the material models. The primary objective of this article is to develop an appropriate strategy to address this issue. We show that both the series and the parallel connection between two rheological elements can be modeled within a multiple natural configurations framework without changing or introducing new configurations. The difference in a series and a parallel connection is manifested in the ratio of the stress powers expended during the deformations of the associated rheological elements. Finite deformation version of some well-known rheological models have been used to demonstrate the utility of the proposed theory.
Materials Science (cond-mat.mtrl-sci)
Stability of dipolar bosons in a quasiperiodic potential
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-02-10 20:00 EST
Paolo Molignini, Barnali Chakrabarti
Quasiperiodic potentials and dipolar interactions each impose long-range order in quantum systems, but their interplay unlocks a rich landscape of unexplored quantum phases. In this work, we investigate how dipolar bosonic crystals respond to correlated disorder in the form of quasiperiodic potentials. Using exact numerical simulations and a suite of observables - including order parameters, energy, density distributions, and two-body coherence measures - we explore one-dimensional dipolar bosons in quasiperiodic lattices at both commensurate and incommensurate fillings. Our results reveal a complex competition between superfluid, Mott insulator, density-wave, and crystalline phases, governed by the intricate balance of dipolar interactions, kinetic energy, and disorder strength. Crucially, we identify mechanisms that influence dipolar crystals, showing their surprising robustness even in the presence of strong quasiperiodic disorder. Strikingly, we challenge previous claims by demonstrating that a kinetic crystal phase - expected to precede full crystallization - does not emerge in the ground state. Instead, its traits appear only under moderate disorder, but never fully develop, giving way to a direct transition from a charge density wave to a crystal state. These findings provide new insights into the resilience of many-body quantum phases in complex environments and pave the way for engineering exotic quantum states in ultracold atomic systems.
Quantum Gases (cond-mat.quant-gas), Disordered Systems and Neural Networks (cond-mat.dis-nn), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
17 pages, 14 figures; comments welcome
Quantum noise spectroscopy of superconducting critical dynamics and vortex fluctuations in a high-temperature cuprate
New Submission | Superconductivity (cond-mat.supr-con) | 2025-02-10 20:00 EST
Zhongyuan Liu, Ruotian Gong, Jaewon Kim, Oriana K. Diessel, Qiaozhi Xu, Zack Rehfuss, Xinyi Du, Guanghui He, Abhishek Singh, Yun Suk Eo, Erik A. Henriksen, G. D. Gu, Norman Y. Yao, Francisco Machado, Sheng Ran, Shubhayu Chatterjee, Chong Zu
Characterizing the low-energy dynamics of quantum materials is crucial to our understanding of strongly correlated electronic states. However, extracting universal dynamical features requires resolving correlations at both low energy and momentum. Here, we introduce nitrogen-vacancy (NV) centers in diamond as a novel and powerful quantum sensing platform of superconducting materials. We demonstrate the strengths of our approach by probing several low-energy phenomena in high-\(T_c\) cuprate Bi\(_2\)Sr\(_2\)CaCu\(_2\)O\(_{8+\delta}\) (BSCCO) -- gapless quasiparticle excitations, critical fluctuations at the metal-superconductor transition and kinetics of vortices. In the absence of an applied magnetic field, we find a sharp reduction in the NV relaxation time (\(T_1\)) near the critical temperature \(T_c\approx90~\)K, attributed to supercurrent-fluctuation induced magnetic noise. Crucially, the temperature-scaling of the noise near criticality deviates from the Bardeen-Cooper-Schrieffer (BCS) mean-field prediction and reflects critical order parameter fluctuations, allowing us to determine both static and dynamical critical exponents for the transition. When a small field is applied, we detect a broad and asymmetric reduction of \(T_1\) near \(T_c\), indicating significant field-induced smearing of the transition. By analyzing the scaling of the BSCCO-induced relaxation rate with the field strength, we unveil evidence in favor of a vortex liquid phase. Finally, deep inside the superconducting phase, we employ NV decoherence (\(T_2\)) spectroscopy to observe strong magnetic fluctuations in the low-frequency regime, suggesting the presence of complex vortex-solid fluctuations. Our results establish NV-based noise spectroscopy as a versatile platform for probing dynamical phenomena in superconductors, with frequency and length scales complementary to existing techniques.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
9 pages, 4 figures in main text
Chiral Instabilities in Driven-Dissipative Quantum Liquids
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-02-10 20:00 EST
Zhi-Xing Lin, Bastien Lapierre, Per Moosavi, Shinsei Ryu
We investigate the nonequilibrium dynamics of periodically driven Tomonaga-Luttinger liquids (TLLs) coupled to a thermal bath using a Floquet-Lindblad approach. When the coupling to the bath satisfies detailed balance, we obtain a condition for parametric instabilities to be suppressed, symmetrically for both chiralities. Remarkably, by designing a purely chiral coupling to the bath, instead of instability suppression, we uncover a driven-dissipative phase transition between the former symmetric parametric instability and a new chiral parametric instability. In the latter, a single chirality of bosonic quasiparticles gets exponentially amplified, leading to a dynamical chiral imbalance within the TLL, reminiscent of the non-Hermitian skin effect.
Statistical Mechanics (cond-mat.stat-mech), Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el)
10 pages + SM, RevTeX, 5 figures
A comparison of phase field models of brittle fracture incorporating strength: I -- Mixed-mode loading
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Umar Khayaz, Aarosh Dahal, Aditya Kumar
The classical variational phase-field model for brittle fracture effectively predicts the growth of large pre-existing cracks. However, the modeling of crack nucleation continues to be a significant challenge. Crack nucleation under uniform stress depends on the material's strength surface whose description is fundamentally incompatible with the energy-based Griffith propagation criterion. To address this, three main phase-field approaches have emerged, each attempting to reconcile material strength and toughness. The first, known as the classical variational approach, preserves the variational structure but fails to accurately incorporate the strength surface. In contrast, the other two approaches -- the complete nucleation and hybrid cohesive zone models -- sacrifice variational consistency. Among these, only the complete nucleation approach precisely accounts for the strength surface. All three approaches, especially the second one, deviate from the sharp variational theory of brittle fracture, raising concerns about their reliability in predicting the growth of cracks under non-mode-I loading. This paper evaluates precisely this issue. It is the first in a series of studies comparing the three approaches, systematically investigating crack growth under mode II, mode III, and mixed-mode loadings. The results confirm that the complete nucleation approach effectively predicts crack growth across all investigated problems, and its predictions agree well with those from other two approaches for tension-dominated cases. Additionally, the findings highlight that inaccurate accounting of the strength surface in the classical variational approach can influence crack path predictions. Lastly, they reveal that modifying the crack driving force to incorporate the strength surface in the hybrid cohesive zone approach causes crack propagation at an incorrect fracture toughness.
Materials Science (cond-mat.mtrl-sci)
Enhanced chemical vapour deposition of monolayer MoS2 films via a clean promoter
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Lulin Wang, Yue Sun, Kaushik Kannan, Lee Gannon, Xuyun Guo, Aran Rafferty, Karl Gaff, Navaj B. Mullani, Haizhong Weng, Yangbo Zhou, Valeria Nicolosi, Cormac Mc Guinness, Hongzhou Zhang
Two-dimensional (2D) transition metal dichalcogenides (TMDCs), exemplified by molybdenum disulfide (MoS2), have shown exceptional potential for data-centred, energy-efficient electronic applications due to their unique electrical, optoelectronic, and mechanical properties. However, challenges such as the controllable synthesis of high-quality, large-area 2D MoS2 films and the mitigation of contamination during growth remain significant barriers to their integration into advanced technologies. Here, we developed a novel contamination-free growth promoter, enabling the clean and scalable synthesis of high quality 2D MoS2 with desirable grain structures via chemical vapour deposition (CVD). By optimising the reactant concentration and S/Mo ratio, we achieved promoter-dominated enhanced growth with enhanced quality, as evidenced by the increased MoS2 flake size and coverage, alongside a strong PL A exciton peak at 1.84 eV, matching that of the mechanically exfoliated sample. This approach facilitates the clean and site-specific growth of high-quality 2D MoS2, establishing a robust pathway for the practical implementation of 2D MoS2 in next-generation electronic devices.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
27 pages, 4 figures
Evidence of Athermal Metastable Phase in a Halide Perovskite: Optically Tracked Thermal-Breach Memory
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Kingshuk Mukhuti, Satyaki Kundu, Debasmita Pariari, Deepesh Kalauni, Ashutosh Mohanty, Aniket Bajaj, D. D. Sarma, Bhavtosh Bansal
Halide perovskite materials have been extensively studied in the last decade because of their impressive optoelectronic properties. However, their one characteristic that is uncommon for semiconductors is that many undergo thermally induced structural phase transitions. The transition is hysteretic, with the hysteresis window marking the boundary of the metastable phase. We have discovered that in methylammonium lead iodide, this hysteretic metastable phase is athermal, meaning it shows almost no temporal phase evolution under isothermal conditions. We also show that a large number of distinguishable metastable states can be prepared following different thermal pathways. Furthermore, under a reversible thermal perturbation, the states in the metastable phase either show return-point memory or undergo a systematic nonrecoverable phase evolution, depending on the thermal history and the sign of the temperature perturbation. Since the phase fraction can be probed with extreme sensitivity via luminescence, we have an optically retrievable memory that reliably records any breach in temperature stability. Such thermal-breach memory in athermal martensites, of which there are numerous examples, may be useful for tagging packages requiring strict temperature control during transportation or preservation.
Materials Science (cond-mat.mtrl-sci)
21 Pages, 21 figures
Strongly dispersive dielectric properties of high-ScN-fraction ScAlN deposited by molecular beam epitaxy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Vikrant J. Gokhale, James G. Champlain, Matthew T. Hardy, James L. Hart, Andrew C. Lang, Saikat Mukhopadhyay, Jason A. Roussos, Shawn C. Mack, Gabriel Giribaldi, Luca Colombo, Matteo Rinaldi, Brian P. Downey
We present a comprehensive study of dielectric properties including complex permittivity, loss, and leakage of high-ScN-fraction ScAlN thin films grown using molecular beam epitaxy (MBE). Dielectric spectroscopy is carried out on high-ScN-fraction (30%-40% ScN fraction) samples from 20 Hz to 10 GHz. We find that real permittivity {}' increases significantly with increasing ScN fraction; a trend confirmed by density functional theory. Further, {}' is strongly dispersive with frequency and increasing ScN fraction, with values for Sc0.4Al0.6N varying from 150 down to 60 with increasing frequency. Loss, dispersion, and DC leakage current correspondingly increase with ScN fraction. The high {}' and strongly dispersive behavior in MBE ScAlN are not observed in a sputter-deposited ScAlN control with a similar ScN fraction, highlighting fundamental differences between films produced by the two deposition methods. Microscopy and spectroscopy analyses are carried out on MBE- and sputter-deposited samples to compare microstructure, alloy, and dopant concentration.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Direct Visualization of Temperature-Induced Phase Separation of Completely Miscible Au-Pd Alloy by In-Situ TEM
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Abhijit Roy, Simon Hettler, Raul Arenal
In-situ transmission electron microscopy (TEM) studies reveal key insights into the structural and chemical evolution of nanoparticles (NPs) under external stimuli like heating and biasing, which is critical for evaluating their suitability in chemical reactions and their tendency towards forming novel NP systems. In this study, starting from a core@shell Au nanotriangle (AuNT)@Pd nanostructure, the formation of a phase-separated bi-metallic Au-Pd NP system at high temperature is reported, despite the fact that Au and Pd are miscible in the entire composition and temperature range. In-situ TEM heating of bare AuNT@Pd core@shell structures up to 1000°C has been performed. Between 400°C and 800°C, an initial alloy formation has been observed. It is also noted that higher initial loading of Pd increases the melting temperature of the bi-metallic system. However, the most important observation is the separation of the nanostructure into Au and Pd phases at temperatures higher than 850° C for high Pd doping. The extent of Pd separation depends on the amount of initial Pd loading. A Janus Au-Pd nanostructure is formed at the end of the thermal treatments at 1000° C. The phase-separated NP is observed to be highly stable and could be clearly beneficial for various applications, particularly in catalytic processes.
Materials Science (cond-mat.mtrl-sci)
Small 2408109 (2025)
Generalized \(\eta\)-pairing theory and anomalous localization in non-Hermitian systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-02-10 20:00 EST
By generalizing the eta-pairing theory to non-Hermitian Hubbard models on arbitrary lattices, we obtain the sufficient and necessary condition for the eta-pairing operator to be an eigenoperator of the Hamiltonian \(H\), and find unique eta-pairing phenomena without Hermitian analogs. For instance, the Hermitian conjugate of an eta-pairing eigenoperator may not be an eigenoperator, eta-pairing eigenoperators can be spatially modulated, and the \(SU(2)\) pseudospin symmetry may not be respected even if \(H\) commutes with the eta-pairing operators. Remarkably, these novel non-Hermitian phenomena are closely related to each other by several theorems we establish and can lead to, e.g., the notion of non-Hermitian angular-momentum operators and the anomalous localization of eta-pairing eigenstates. Some issues on the \(SO(4)\) and particle-hole symmetries are clarified. Our general eta-pairing theory also reveals a previously unnoticed unification of these symmetries of the Hubbard model. To exemplify these findings, we propose the Hatano-Nelson-Hubbard model. In this interacting non-Hermitian system without even the bulk translation invariance, the right and left two-particle eta-pairing eigenstates are exponentially localized at opposite boundaries of the chain. We then generalize this model to two dimensions and find that the eta-pairing eigenstate can exhibit the first- or second-order skin effect. Thus, eta-pairing may represent a new mechanism for skin effects in interacting non-Hermitian systems, even in higher dimensions and without the bulk translation symmetry. To realize all of the non-Hermitian eta-pairing phenomena, we construct a general two-sublattice model defined on an arbitrary lattice, which can exhibit anomalous localization of eta-pairing eigenstates; besides, this model can reveal the eta-pairing structure [e.g., the \(SO(4)\) symmetry] in systems with Hermitian hoppings.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
39 pages
Giant coercivity and enhanced intrinsic anomalous Hall effect at vanishing magnetization in a compensated kagome ferrimagnet
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-02-10 20:00 EST
Jonathan M. DeStefano, Elliott Rosenberg, Guodong Ren, Yongbin Lee, Zhenhua Ning, Olivia Peek, Kamal Harrison, Saiful I. Khondaker, Liqin Ke, Igor I. Mazin, Juan Carlos Idrobo, Jiun-Haw Chu
Ferrimagnets that can be driven to magnetic compensation show promise for use in spintronics as they exhibit a finite anomalous Hall effect at zero magnetic field without having a significant magnetic moment. Compensated ferrimagnet spintronic devices with both a large anomalous Hall effect and a high coercivity would be simultaneously easy to read and difficult to erase. The kagome ferrimagnet TbMn\(_6\)Sn\(_6\) has been reported to host a large intrinsic anomalous Hall effect. Here, we demonstrate that doping the Mn sites with Cr drives the system towards magnetic compensation. For nearly compensated compositions at low temperatures, giant coercive fields exceeding 14 T are observed. Additionally, Cr doping significantly enhances the intrinsic anomalous Hall effect, which can be attributed to a shift in the Fermi level. Our results extend the range of unique magnetic states observed in kagome materials, demonstrating that chemical doping is an effective strategy to tune and realize these states.
Strongly Correlated Electrons (cond-mat.str-el)
Visualizing Field-free Deterministic Magnetic Switching of all-van der Waals Spin-Orbit Torque System Using Spin Ensembles in Hexagonal Boron Nitride
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Xi Zhang, Jingcheng Zhou, Chaowei Hu, Kuangyin Deng, Chuangtang Wang, Nishkarsh Agarwal, Hanshang Jin, Faris A. Al-Matouq, Stelo Xu, Roshan S. Trivedi, Senlei Li, Sumedh Rathi, Hanyi Lu, Zhigang Jiang, Valentin Taufour, Robert Hovden, Liuyan Zhao, Ran Cheng, Xiaodong Xu, Jiun-Haw Chu, Chunhui Rita Du, Hailong Wang
Recently, optically active spin defects embedded in van der Waals (vdW) crystals have emerged as a transformative quantum sensing platform to explore cutting-edge materials science and quantum physics. Taking advantage of excellent solid-state integrability, this new class of spin defects can be arranged in controllable nanoscale proximity of target materials in vdW heterostructures, showing great promise for improving spatial resolution and field sensitivity of current sensing technologies. Building on this state-of-the-art measurement platform, here we report hexagonal boron nitride-based quantum imaging of field-free deterministic magnetic switching of room-temperature two-dimensional magnet Fe3GaTe2 in an all-vdW spin-orbit torque (SOT) system. By visualizing SOT-driven variations of nanoscale Fe3GaTe2 magnetic stray field profile under different conditions, we have revealed how the observed magnetic switching evolves from deterministic to indeterministic behavior due to the interplay between out-of-plane spins, in-plane spins and Joule heating. This understanding, which is otherwise difficult to access by conventional transport measurements, offers valuable insights on material design, testing, and evaluation of next-generation vdW spintronic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
13 pages, 4 figures
Fundamental Factors Governing Stabilization of Janus 2D-Bulk Heterostructures with Machine Learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Tara M. Boland (Technical University of Denmark), Rachel Gorelik (Arizona State University), Arunima K. Singh (Arizona State University)
The more-than-6000 2D materials predicted thus far provide a huge combinatorial space for forming functional heterostructures with bulk materials, with potential applications in nanoelectronics, sensing, and energy conversion. In this work, we investigate nearly 1000 heterostructures, the largest number of heterostructures thus far, of 2D Janus and bulk materials' surfaces using ab initio simulations and machine learning (ML) to deduce the structure-property relationships of the complex interfaces in such heterostructures. We first perform van der Waals-corrected density functional theory simulations using a high-throughput computational framework on 51 Janus 2D materials and 19 metallic, cubic phase, elemental bulk materials that exhibit low lattice mismatches and low coincident site lattices. The formation energy of the resultant 1147 Janus 2D-bulk heterostructures were analyzed and 828 were found to be thermodynamically stable. ML models were trained on the computed data, and we found that they could predict the binding energy and \(z\)-separation of 2D-bulk heterostructures with root mean squared errors (RMSE) of 0.05 eV/atom and 0.14 angstroms, respectively. The feature importance of the models reveals that the properties of the bulk materials dominate the heterostructures' energies and interfacial structures heavily. These findings are in-line with experimentally observed behavior of several well-known 2D materials-bulk systems. The data used within this paper is freely available in the Ab Initio 2D-Bulk Heterostructure Database (aiHD). The fundamental insights on 2D-bulk heterostructures and the predictive ML models developed in this work could accelerate the application of thousands of 2D-bulk heterostructures, thus stimulating research within a wide range of electronic, quantum computing, sensing, and energy applications.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 figures
Laser-driven Ultrafast Dynamics of a Fractional Quantum Hall System
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Ammar Kirmani, Benedikt Fauseweh, Jian-Xin Zhu
Fractional quantum Hall (FQH) systems are strongly interacting electron systems with topological order. These systems are characterized by novel ground states, fractionally charged and neutral excitations. The neutral excitations are dominated by a low-energy collective magnetoroton mode. Here we derive and use a quasi-one-dimensional model to investigate the ultrafast nonequilibrium dynamics of a laser-driven FQH system within a two-Landau-level approximation. As opposed to the traditional and synthetic bilayers, our model accounts for interactions where electrons can scatter from one Landau-level to another. By performing exact time evolution of the system, we create an out-of-equilibrium state following the laser pulse that shows rich physics. Our calculations show the presence of non-trivial excited modes. One of these modes is electromagnetically active and represent density oscillations of mode. Another mode is identified by evaluating the overlap of the initial state and the out-of-equilibrium state following the laser pulse with a quadrupole operator. This mode is analogous to the chiral-graviton mode for FQH systems recently measured in experiments [Nature {}, 78 (2024)]. Our results show that a linearly-polarized pulse field can excite the graviton mode when inter-Landau level scattering occurs.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
Pure momentum-shift bulk photovoltaic effect in ferroelectric flat-band Mott insulators
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Zhuocheng Lu, Zhihao Gong, Jingshan Qi, Hua Wang, Kai Chang
The shift current photovoltaic effect is conventionally understood as the real-space displacement of a wave packet induced by photoexcitation. However, this interpretation becomes insufficient in flat-band systems, where quasiparticles are too massive to accelerate in real space under the optical electric field. Here, we developed a gauge-invariant method to decompose the shift current into real-space and momentum-space components. A surprising pure momentum-space shift current is found theoretically in flat-band Mott insulator Nb3X8 (X = Cl, Br, I) monolayers. This work underscores that significant shift current responses can emerge even in systems with minimal interband polarization differences, highlighting the potential for exploring novel bulk photovoltaic effects in flat-band Mott insulators.
Materials Science (cond-mat.mtrl-sci)
Self-limiting states of polar misfits: Frustrated assembly of warped-jigsaw particles
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-02-10 20:00 EST
Michael Wang, Gregory M. Grason
We study the ground state thermodynamics of a model class of geometrically frustrated assemblies, known as {} particles. While it is known that frustration in soft matter assemblies has the ability to propagate up to mesoscopic, multi-particle size scales, notably through the selection of self-limiting domain, little is understood about how the symmetry of shape-misfit at the particle scale influences emergent morphologies at the mesoscale. Here we show that polarity in the shape-misfit of warped-jigsaw puzzles manifests at a larger scale in the morphology and thermodynamics of the ground-state assembly of self-limiting domains. We use a combination of continuum theory and discrete particle simulations to show that the polar misfit gives rise to two mesoscopically distinct polar, self-limiting ribbon domains. Thermodynamic selection between the two ribbon morphologies is controlled by a combination of the binding anisotropy along distinct neighbor directions and the orientation of polar shape-misfit. These predictions are valuable as design features for ongoing efforts to program self-limiting assemblies through the synthesis of intentionally frustrated particles, and further suggests a generic classification of frustrated assembly behavior in terms of the relative symmetries of shape-misfit and the underlying long-range inter-particle order it frustrates.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
24 pages, 10 figures, 4 appendices
Derivation of d-wave symmetry in real-space superconductors
New Submission | Superconductivity (cond-mat.supr-con) | 2025-02-10 20:00 EST
A simple derivation of \(d\)-wave order parameter within the real-space pairing and Bose-Einstein condensation mechanism of superconductivity is given. The two key ingredients are a short-range attraction between carriers and hole-like hopping between equal-energy pair configurations.
Superconductivity (cond-mat.supr-con)
A note. 4 pages, 2 figures
Beyond the Bethe-Salpeter equation in DFT based computational spectroscopy
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-02-10 20:00 EST
Alessandro Mirone, Mauro Rovezzi, Christoph Sahle, Alessandro Longo
We introduce a theoretical framework that accurately describes resonances beyond the reach of both multiplet-based and density-functional-theory (DFT)-based codes. When a resonance acquires strong continuum character, multiplet approaches struggle with the exponential growth of the Hilbert space driven by the increasing number of relevant orbitals, if they extend beyond a few atomic and ligand orbitals. Conversely, existing codes, supplemented by diagrammatic techniques, remain largely confined to the Bethe--Salpeter equation, which tracks only two-particle excitations. However, many systems of interest, particularly those containing open \(d\) or \(f\) shells, require the propagation of an \(N\)-particle system, yielding a richer spectral landscape dominated by significant continuum effects. Here, we propose a theoretical framework, together with its numerical implementation, that bridges this gap and enables the rigorous exploration of such resonances.
Strongly Correlated Electrons (cond-mat.str-el)
Coherent spin dynamics in ensembles of randomly oriented singly charged colloidal nanoplatelets and nanocrystals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Aleksandr A. Golovatenko, Anna V. Rodina
We present a theoretical study of the pump-probe Faraday rotation and ellipticity signals in ensembles of uniaxially anisotropic CdSe nanoplatelets and nanocrystals. We use the Faraday rotation mechanism based on the excitation of negative heavy hole trions for a magnetic field applied in the Voigt geometry. Three types of ensembles with typical spatial distributions of the orientation of the anisotropy axis with respect to the direction of light propagation are considered. Faraday rotation and ellipticity signals are modeled for excitation by single and repeated pump pulses, taking into account the anisotropy of the electron g-factor. We show that spin dephasing caused by the electron g-factor anisotropy and the arbitrary orientation of nanoplatelets or nanocrystals result only in partial damping of oscillation amplitude in contrast to the dephasing caused by the dispersion of the electron g-factor in the ensemble. We demonstrate that regardless of the g-factor anisotropy degree the oscillation frequency of the Faraday rotation and ellipticity signals for a randomly oriented ensemble is determined by the transverse electron g-factor component.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
13 pages, 6 figures
Mixed-symmetry superconductivity and the energy gap
New Submission | Superconductivity (cond-mat.supr-con) | 2025-02-10 20:00 EST
Pramodh Senarath Yapa, Xinyu Guo, Joseph Maciejko, Frank Marsiglio
The symmetry of the superconducting order parameter, or simply the ``gap'', provides certain constraints on the actual mechanism that gives rise to pairing and ultimately to superconductivity. In this work we continue to investigate the possible symmetries that can arise, particularly below \(T_c\), for a generic tight-binding model. We first examine the 1D case to better illustrate the prevalence of symmetry-breaking transitions below \(T_c\), and then the more realistic 2D case. In both cases we illustrate the implication for spectroscopic investigations of the energy gap by calculating the density of states for different temperatures below \(T_c\). The result is a very different signature near \(T_c\) compared to that near \(T=0\). A complete picture of the superconducting symmetry can only be attained if measurements are made over the entire temperature range.
Superconductivity (cond-mat.supr-con)
15 pages, 17 figures. We wish to acknowledge the memory of Jan Zaanen with this manuscript. His animated discussion of a multitude of topics at conferences and accompanying meals will always be remembered. His enthusiasm for discovery and for "new ways of thinking about things'' remain an inspiration for those who knew him
Enskog and Enskog-Vlasov equations with a slightly modified correlation factor and their H theorem
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-02-10 20:00 EST
Shigeru Takata, Aoto Takahashi
A novel modification of the original Enskog equation is proposed. The modification is much simpler than that is made in the modified (or revised) Enskog equation proposed by van Beijeren & Ernst in 1973 and does not require a consideration of many-body configuration. The proposed modification is general enough to be adapted to various equations of states for non-ideal gases. It is shown that the H-theorem can be established for the Enskog and the Enskog--Vlasov equation with the proposed modification.
Statistical Mechanics (cond-mat.stat-mech), Mathematical Physics (math-ph)
26 pages, No figures
Probing the flat-band limit of the superconducting proximity effect in Twisted Bilayer Graphene Josephson junctions
New Submission | Superconductivity (cond-mat.supr-con) | 2025-02-10 20:00 EST
A. Diez-Carlon, J. Diez-Merida, P. Rout, D. Sedov, P. Virtanen, S. Banerjee, R. P. S. Penttila, P. Altpeter, K. Watanabe, T. Taniguchi, S.-Y. Yang, K. T. Law, T. T. Heikkila, P. Torma, M. S. Scheurer, D. K. Efetov
While extensively studied in normal metals, semimetals and semiconductors, the superconducting (SC) proximity effect remains elusive in the emerging field of flat-band systems. In this study we probe proximity-induced superconductivity in Josephson junctions (JJs) formed between superconducting NbTiN electrodes and twisted bilayer graphene (TBG) weak links. Here the TBG acts as a highly tunable topological flat-band system, which due to its twist-angle dependent bandwidth, allows to probe the SC proximity effect at the crossover from the dispersive to the flat-band limit. Contrary to our original expectations, we find that the SC remains strong even in the flat-band limit, and gives rise to broad, dome shaped SC regions, in the filling dependent phase diagram. In addition, we find that unlike in conventional JJs, the critical current Ic strongly deviates from a scaling with the normal state conductance GN. We attribute these findings to the onset of strong electron interactions, which can give rise to an excess critical current, and also work out the potential importance of quantum geometric terms as well as multiband pairing mechanisms. Our results present the first detailed study of the SC proximity effect in the flat-band limit and shed new light on the mechanisms that drive the formation of SC domes in flat-band systems.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
Unified description of viscous, viscoelastic, or elastic thin active films on substrates
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-02-10 20:00 EST
Henning Reinken, Andreas M. Menzel
It is frequent for active or living entities to find themselves embedded in a surrounding medium. Resulting composite systems are usually classified as either active fluids or active solids. Yet, in reality, particularly in the biological context, a broad spectrum of viscoelasticity exists in between these two limits. There, both viscous and elastic properties are combined. To bridge the gap between active fluids and active solids, we here systematically derive a unified continuum-theoretical framework. It covers viscous, viscoelastic, and elastic active materials. Our continuum equations are obtained by coarse-graining a discrete, agent-based microscopic dynamic description. In our subsequent analysis, we mainly focus on thin active films on supporting substrates. Strength of activity and degree of elasticity are used as control parameters that control the overall behavior. We concentrate on the analysis of transitions between spatially uniform analytical solutions of collective migration. These include isotropic and polar, orientationally ordered states. A stationary polar solution of persistent directed collective motion is observed for rather fluid-like systems. It corresponds to the ubiquitous swarming state observed in various kinds of dry and wet active matter. With increasing elasticity, persistent motion in one direction is prevented by elastic anchoring and restoring forces. As a consequence, rotations of the spatially uniform migration direction and associated flow occur. Our unified description allows to continuously tune the material behavior from viscous, via viscoelastic, to elastic active behavior by variation of a single parameter. Therefore, it allows in the future to investigate the time evolution of complex systems and biomaterials such as biofilms within one framework.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph), Fluid Dynamics (physics.flu-dyn)
Interplay of Kondo Physics with Incommensurate Charge Density Waves in CeTe\(_3\)
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-02-10 20:00 EST
Vesna Miksic Trontl, Ilya I. Klimovskikh, Asish K. Kumar, Denis V. Vyalikh, Alex Louat, Cephise Cacho, Elio Vescovo, Ivana Vobornik, Cedomir Petrovic, Tonica Valla
CeTe\(_3\) is a 2-dimensional (2D) Van der Waals (VdW) material with incommensurate charge density waves (CDW), extremely high transition temperature (\(T_{CDW}\)) and a large momentum-dependent CDW gap that leaves a significant portion of the Fermi surface intact. It is also considered to be a weak Kondo system, a property unexpected for a material with incommensurate CDW, where each atomic site is slightly different. Here, we study the properties of the CDW state in several RTe\(_3\) (R is rare earth) materials and examine the hybridization of itinerant states with the localized Ce \(4f\) multiplet in CeTe\(_3\) by using angle resolved photoemission spectroscopy (ARPES). We find that the renormalization of the itinerant states originating from the hybridization with the localized \(4f\) states at \(-260\) meV extends to the Fermi level. This, with remnants of another localized state at the Fermi level, supports the characterization of CeTe\(_3\) as a weak Kondo material. Furthermore, we uncover a \(k\)-dependence of the hybridization with the states \(-260\) meV, indicating that similar effect could be the reason for discrepancy between the heavy masses in specific heat and light ones in Shubnikov de Haas oscillations observed in other heavy fermion materials.
Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 3 figures
Wannier interpolation of spin accumulation coefficient
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
The spin Hall (SH) effect is widely understood as a phenomoenon in which spin current flows perpendicular to an electric field. In the presence of a spin-orbit coupling, however, spin current is ambiguous, and the SH conductivity depends on the definition of spin current. In this article, we develop an computational scheme for the spin accumulation coefficient, which characterizes the spin accumulation and would be an alternative indicator of the SH effect. The proposed method has been implemented into an open-source software Wannier90 and serves high-precision research on the SH effect.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
7 pages, 4 figures
Open system dynamics in linear-time beyond the wide-band limit
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Yaroslav Pavlyukh, Riku Tuovinen
Nonequilibrium heat transport in quantum systems coupled to wide-band embeddings provides a striking example of the limitations of the generalized Kadanoff-Baym ansatz (GKBA), while solving the full two-time Kadanoff-Baym equations remains computationally prohibitive. To address this challenge, we propose an iterated solution to the reconstruction problem, resulting in a time-linear evolution scheme involving 14 correlators for systems with narrow-band embeddings. This approach eliminates GKBA-related artifacts and resolves convergence issues associated with the wide-band limit. Furthermore, it enables the calculation of energy- and time-resolved currents, facilitating the modeling of heat flows in quantum systems and energy- and time-resolved photoemission experiments, all at significantly reduced computational cost.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
6 pages, 4 figures
Contact value theorem for electric double layers with modulated surface charge density
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-02-10 20:00 EST
The contact value theorem was originally derived for Coulomb fluids of mobile charged particles in thermal equilibrium, in the presence of interfaces carrying a {} surface charge density and in the absence of dielectric discontinuities. It relates the pressure (the effective force) between two parallel electric double layers to the particle number density and the surface charge density at the interface, separately for each of the two electric double layers. In this paper, we generalise the contact value theorem to electric double layers with interfaces carrying a {} surface charge density. The derivation is based on balance of forces exerted on interfaces. The relevance of particular terms of the contact value theorem is tested on an exactly solvable two-dimensional Coulomb system with counterions only at the coupling constant \(\Gamma=2\).
Statistical Mechanics (cond-mat.stat-mech)
23 pages, 3 figures
J. Phys. A: Math. Theor. 58 (2025) 065001
Crossover from Wannier-Stark localization to charge density waves for interacting spinless fermions in one dimension
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-02-10 20:00 EST
Nair Aucar Boidi, Amnon Aharony, Ora Entin-Wohlman, Karen Hallberg, Cesar Proetto
We study spinless fermions on a finite chain with nearest-neighbor
repulsion and in the presence of a Wannier-Stark linearly-varying
electric field potential. In the absence of the interaction, the
eigenstates are localized for the system's sizes larger than the
localization length. We present several analytical expressions for the
localization length, which is proportional to the inverse of the
electric field. Using the density matrix renormalization group numerical
technique, we observe that the ground state exhibits a decrease of the
occupation on the chain sites from the
bulk', with occupation 1, to the vacuum, with occupation 0. The width of this intermediateedge'
region is also inversely proportional to the electric field, increasing
linearly with the strength of the nearest-neighbor repulsion. For strong
interactions, the occupations in the intermediate region exhibit a
charge density wave. We also present the local density of states for
sites in the `edge' region. For the non-interacting case, the spectrum
shows an increasing energy-localized structure as the field is
increased, which is a consequence of the uniform energy distribution of
the localized states (Wannier-Stark ladder). This structure survives for
small interactions, and it smears out in the strongly interacting limit.
Experimental variations of the slope of the potential (the electric
field) on cold atom chains may test these predictions.
Strongly Correlated Electrons (cond-mat.str-el)
Anomalous Knudsen effect signaling long-lived modes in 2D electron gases
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Grigory A. Starkov, Björn Trauzettel
Proper analysis of electron collisions in two spatial dimensions leads to the conclusion, that the odd harmonics of the electron distribution function decay much slower than the even ones at finite temperatures. The number of long-lived odd harmonics quickly shrinks with increasing temperature. Focusing on a channel geometry with boundary scattering, we show that such behavior of the odd decay rates leads to a characteristic behaviour of the conductance that we dub anomalous Knudsen effect: it initially grows with temperature but then starts to decrease, forming a peak. Further increase of the temperature forces the conductance to grow again due to the Gurzhi effect, associated with the crossover from ballistic to hydrodynamic transport. The simultaneous observation of the Gurzhi dip preceded by the anomalous Knudsen peak constitutes a particular signature of the long-lived modes in 2D electron transport at low temperatures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el)
Sign-reversal and non-monotonicity of chirality-related anomalous Hall effect in highly conductive metals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Ryunosuke Terasawa, Masafumi Udagawa, Hiroaki Ishizuka
The non-monotonic temperature dependence and sign reversal of chirality-related anomalous Hall effect in highly conductive metals are studied. Through the analysis of scattering rate, we find that the non-monotonicity and sign reversal have two major origins: (1) competition between the contribution from short-range and long-range spin correlations and (2) non-monotonic spin correlation in the high field. The former mechanism gives rise to non-monotonic temperature dependence in a wide range of electron density and, in some cases, a sign reversal of Hall resistivity as the temperature decreases. On the other hand, the latter mechanism is responsible for the sign reversal of Hall conductivity in the high field, which sign reversal generally occurs in magnets with antiferromagnetic interactions. The results demonstrate how the Hall effect reflects local spin correlation and provide insights into the mechanism of non-monotonicity and sign reversal of the anomalous Hall effect by spin chirality.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 5 figures. Submitted to Physical Review Letters
The non-Abelian geometry, topology, and dynamics of a nonreciprocal Su-Schrieffer-Heeger ladder
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Ziyu Zhou, Zhi-Cong Xu, Li-Jun Lang
Non-Hermiticity breaks down the adiabaticity and naturally leads to the non-Abelian behaviors in multi-band systems. Here we consider a multi-band, non-Hermitian ladder model with the two legs being the nonreciprocal Su-Schrieffer-Heeger chains. We thoroughly study how the non-Abelian geometry, topology, and dynamics emerge in this model at the onset of inter-leg coupling. Under periodic boundary conditions, by defining a gauge-invariant winding number for chiral symmetric systems, we analytically give the exact topological phase diagram. With the aid of underlying symmetries generalized for non-Hermitian systems, we further refine the phase diagram by the geometry of band structure. In the pseudo-Hermitian symmetric regime, we find that the stable non-Abelian dynamics of a Bloch state under an external constant force can be well described in some conditions of the force by the Wilson line constructed for non-Hermitian systems. Under open boundary conditions, we also find that the bulk-boundary correspondence survives in the thermodynamic limit but breaks down for finite-size systems with the leg-dependent non-Hermitian skin effect (NHSE), demonstrating the so-called critical NHSE, of which the decaying length of the bulk skin modes \(\xi\) varies with the system size \(L\) and is numerically verified to satisfy the scale-free power law \(\xi\propto L\). Our work may stimulate more focuses on the non-Abelian properties of the non-Hermitian/open quantum systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
16 pages, 3 figures
Optical orientation of excitons and charged carriers in MAPbI\(_3\) perovskite single crystals in the orthorhombic phase
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Nataliia E. Kopteva, Dmitri R. Yakovlev, Eyüp Yalcin, Ilya A. Akimov, Mladen Kotur, Bekir Turedi, Dmitry N. Dirin, Maksym V. Kovalenko, Manfred Bayer
Optical orientation of exciton and carrier spins by circularly polarized light is the basic phenomenon in the spin physics of semiconductors. Here, we investigate spin orientation in MAPbI3 lead halide perovskite crystals at the cryogenic temperature of 1.6 K, where the material has an orthorhombic crystal structure. The recombination and spin dynamics of excitons and carriers are measured by time-resolved photoluminescence after circularly polarized excitation. The optical orientation of excitons reaches 85%, which persists within their lifetime of 15-80 ps. This high orientation is maintained for excitation laser detunings from the exciton resonance to higher energies by up to 0.3 eV, then decreases and vanishes above 1.5 eV detuning. This indicates that the Dyakonov-Perel spin relaxation mechanism based on inversion symmetry breaking is inactive in MAPbI3 crystals with orthorhombic symmetry. The optical orientation of localized and spatially-separated electrons and holes results in 40% circular polarization of their emission. Their contributions can be identified from the complex spin beats dynamics in transverse magnetic field. The dynamics analysis gives values of the Landé g-factors of 2.83 for electrons and 0.54 for holes. Also, the magnetic-field-induced polarization of excitons and carriers is analyzed in magnetic fields up to 6 T, showing that their spin relaxation times are longer than their lifetimes. Namely, for the excitons, the spin relaxation time exceeds the lifetime by a factor of 6. We model the dynamics of optical orientation degree for cumulative contributions of excitons and carriers and show that the exciton recombination dynamics can control these dynamics. The polarized emission of excitons and localized carriers, produced by their polarization on Zeeman-split levels in magnetic fields, is modeled.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Kerr non-linearity enhances the response of a graphene Josephson bolometer
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Joydip Sarkar, Krishnendu Maji, Abhishek Sunamudi, Heena Agarwal, Priyanka Samanta, Anirban Bhattacharjee, Rishiraj Rajkhowa, Meghan P. Patankar, Kenji Watanabe, Takashi Taniguchi, Mandar M. Deshmukh
Highly sensitive, broadband bolometers are of great interest because of their versatile usage in wide areas starting from dark matter search, radio astronomy, material science, and qubit readouts in cQED experiments. There have been different realizations of bolometers using superconducting thin films, nanowires, quantum dots, and various 2D materials in the recent past. The challenge is to have a single device that combines high sensitivity, broad bandwidth, a fast readout mechanism, and low noise. Here we demonstrate the first usage of a Josephson parametric amplifier (JPA) as a highly sensitive bolometer. Our key finding is the Kerr non-linearity of the JPA boosts the device's sensitivity. When the bolometer is biased in the non-linear regime, it enhances the sideband signals (~100 times), resulting in an order of magnitude improvement in sensitivity compared to the linear regime. In the non-linear biasing of the device, we achieve a NEP~500 aW/sqrt(Hz). Our bolometer offers a fast detection scheme with a thermal time constant of 4.26 us and an intrinsic JPA time constant of 70 ns. Our device's broadband and fast operation are key and new compared to previously studied graphene-based bolometers. In our device, the gate voltage tunability and the possibility of multiplexing combined with the sensitive bolometric performance offer an opportunity for integrated quantum sensor arrays. Our work demonstrates a way forward to enhance the performance of quantum sensors based on 2D materials by leveraging the inherent non-linear response.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Spin dynamics and magnetic excitations of quasi-1D spin chain Ca\(_3\)ZnMnO\(_6\)
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-02-10 20:00 EST
Suheon Lee, D. T. Adroja, Qing Zhang, Gheorghe Lucian Pascut, Kristjan Haule, A.D. Hillier, M. Telling, W. Kockelmann, Sang-Wook Cheong, K.-Y. Choi
To reveal the structure-property relationship in quasi-one-dimensional (1D) spin-chain system Ca\(_3\)ZnMnO\(_6\), we present comprehensive results, combining basic physical characterizations such as muon spin relaxation/rotation (\(\mu\)SR), neutron powder diffraction (NPD), inelastic neutron scattering (INS), and theoretical calculations. Ca\(_3\)ZnMnO\(_6\) features a dominant intrachain coupling \(J_1\) and two distinct interchain interactions \(J_2\) and \(J_3\), and it undergoes antiferromagnetic ordering below \(T_{\mathrm{N}}=25\)~K, as revealed by dc magnetic susceptibility and specific-heat measurements. Zero-field \(\mu\)SR shows persistent spin dynamics below \(T_{\mathrm{N}}\), suggesting unconventional magnetic excitations in the ordered state. NPD results indicate a commensurate magnetic ground state with a propagation vector \(\mathbf{k}=0\), where the Mn spins lie in the \(ab\)-plane. INS spectra display dispersive magnetic excitations extending up to about 5~meV, with an energy gap smaller than 0.5~meV. Notably, these spectra exhibit three-dimensional (3D) gapped features rather than the expected 1D behavior, yet spin-wave dispersion analysis confirms an underlying quasi-1D energy hierarchy. We discuss this apparent paradox of 3D-like magnetic excitations in a quasi-1D system in terms of the energy hierarchy modified by nonmagnetic-ion substitution and finite-temperature first-principles calculations. We also suggest that Ca\(_3\)ZnMnO\(_6\) could be a potential candidate for an M-type altermagnet.
Strongly Correlated Electrons (cond-mat.str-el)
15 pages, 14 Figures
Discovery of a large magnetic nonlinear Hall effect in an altermagnet
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Lei Han, Xizhi Fu, Cheng Song, Yuxiang Zhu, Xiaokang Li, Zengwei Zhu, Hua Bai, Ruiyue Chu, Jiankun Dai, Shixuan Liang, Junwei Liu, Feng Pan
Since Edwin Halls groundbreaking discovery of the Hall effect in 1879, magnetism, spin, and quantization have been expanding the scope of Hall effects, continuously driving transformative progress in science and technology. Among them, the latest nonlinear Hall effect (NLHE), where longitudinal electric field tunes quantum geometry to generate nonlinear Hall voltage, attracts wide attention as a sensitive probe of topological phases across a wide range of materials. Here, we report a new Hall effect member: the magnetic nonlinear Hall effect (MNLHE), characterized by a quadratic Hall conductivity dependence on magnetic field, rather than electric field as in NLHE. This finding relies on an altermagnet, Mn5Si3 thin film, whose alternating-sign Berry curvatures ensure higher-order MNLHE clearly distinguishable from the first-order anomalous Hall effect. The observed quadratic dependence originates from chiral next-nearest-neighbor hopping processes that acquire magnetic-exchange-driven Zeeman energies and Haldane-like chiral flux phases. Remarkably, this MNLHE is non-analytic, as reversing the magnetic field flips the alternating spin-splitting bands and reverses the hopping chirality, which is absent in traditional NLHE. Beyond offering a distinctive transport fingerprint for altermagnet Mn5Si3 thin film, this MNLHE is large and unsaturated up to 60 T, providing opportunities for pulsed high-field sensing technologies in both fundamental researches and engineering applications.
Materials Science (cond-mat.mtrl-sci)
27 pages, 4 figures
Observation of non-Hermitian topological disclination states and charge fractionalization
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Ruifeng Li, Rimi Banerjee, Subhaskar Mandal, Da Li, Yang Long, Tianchi Ma, Jianwei Liu, Gui-Geng Liu, Yidong Chong, Baile Zhang, Er-Ping Li
There has been significant interest in exploring topological disclination states, which effectively probe the band topology of the host material beyond the conventional bulk-edge correspondence. While most studies in this area have primarily focused on Hermitian systems, recent theoretical work predicts that non-Hermiticity can drive topological phase transitions and host topological disclination states associated with fractional charge. However, no experimental observations have been reported to date. Here, we report the first experimental observation of topological disclination states in electric circuits, induced solely by gain and loss. Through admittance matrix measurements and eigenstate analysis, we confirm their emergence and compute the corresponding fractional charge. Moreover, the disclination mode profile and localization effect can be directly visualized via monochromatic field excitation. Additionally, we demonstrate the emergence of degenerate zero-energy topological disclination states, devoid of fractional charge, in distinct non-Hermitian geometries. Our findings open the possibility of non-Hermiticity-induced fractional charges in two-dimensional non-Hermitian lattices, which may pave the way for advancements in active topological photonic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
16 pages, 4 figures
Scaling corrections in driven critical dynamics: Application to a two-dimensional dimerized quantum Heisenberg model
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-02-10 20:00 EST
Jing-Wen Liu, Shuai Yin, Yu-Rong Shu
Driven critical dynamics in quantum phase transitions holds significant theoretical importance, and also practical applications in fast-developing quantum devices. While scaling corrections have been shown to play important roles in fully characterizing equilibrium quantum criticality, their impact on nonequilibrium critical dynamics has not been extensively explored. In this work, we investigate the driven critical dynamics in a two-dimensional quantum Heisenberg model. We find that in this model the scaling corrections arising from both finite system size and finite driving rate must be incorporated into the finite-time scaling form in order to properly describe the nonequilibrium scaling behaviors. In addition, improved scaling relations are obtained from the expansion of the full scaling form. We numerically verify these scaling forms and improved scaling relations for different starting states using the nonequilibrium quantum Monte Carlo algorithm.
Statistical Mechanics (cond-mat.stat-mech)
7 pages, 5 figures
Two-Dimensional Lattice-Gas Model for Methane Clathrate Hydrates: Comparative Analysis with Experiments and Three-Dimensional Simulations
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-02-10 20:00 EST
Julian Juan, Maria E. Pronsato, Antonio J. Ramirez-Pastor, Pablo Longone
Methane clathrate hydrates, particularly those with an sI structure, are significant due to their potential as energy resources and their impact on gas pipelines. In this study, a two-dimensional (2D) lattice-gas model is employed to investigate the main thermodynamic properties of methane clathrate hydrates. The proposed framework is validated through comparison with experimental data and more advanced three-dimensional (3D) simulations. Adsorption isotherms, dissociation enthalpy and phase stability of the sI structure are evaluated using Monte Carlo (MC) simulations in the grand canonical ensemble. The 2D adsorption isotherms closely align with both experimental data and 3D simulations, demonstrating the 2D model's ability to precisely represent both rigid and flexible sI structures. The dissociation enthalpy calculated using our approach (76.4 kJ/mol) excellently matches the experimental value (78 kJ/mol), confirming the model's accuracy. Furthermore, the phase diagram obtained from the Clausius-Clapeyron equation shows very good agreement with experimental data between 260 and 290 K, though deviations are observed above 290 K. These findings underscore the effectiveness and robustness of the 2D model in studying methane clathrate hydrates and suggest its potential applicability for investigating other guest species and hydrate structures.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Materials Science (cond-mat.mtrl-sci)
Linear-limit aging times of three monoalcohols
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-02-10 20:00 EST
Jan Philipp Gabriel, Jeppe C. Dyre, Tina Hecksher
This paper presents data for the physical aging of the three monoalcohols 2-ethyl-1-butanol, 5-methyl-2-hexanol, and 1-phenyl-1-propanol. Aging is studied by monitoring how the dielectric loss at a fixed frequency in the kHz range equilibrates upon temperature jumps of a few Kelvin's magnitude from equilibrium to equilibrium. The three alcohols differ in the Debye relaxation strength and how much the Debye relaxation time is different from that of the \(\alpha\) process. We first demonstrate that single-parameter aging describes all data well and proceed to use this to identify linear-limit normalized aging relaxation functions. From the Laplace transform of these functions, the linear-limit aging loss-peak angular frequency defines the inverse of the linear aging relaxation time. This allows for a comparison to the temperature dependence of the Debye and \(\alpha\) dielectric relaxation times of the three monoalcohols. We conclude that the aging response for 5-methyl-2-hexanol and 2-ethyl-1-butanol follows the \(\alpha\) relaxation, not on the Debye process, while no definite conclusion can be reached for 1-phenyl-1-propanol because the Debye and \(\alpha\) relaxations are here too merged to be distinguished.
Soft Condensed Matter (cond-mat.soft)
Chirality-induced spin selectivity based on orbital Edelstein effect in an analytically solvable model
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Börge Göbel, Lennart Schimpf, Ingrid Mertig
Chirality-induced spin selectivity, a phenomenon wherein chiral structures selectively determine the spin polarization of electron currents flowing through the material, has garnered significant attention due to its potential applications in areas such as spintronics, enantioseparation, and catalysis. The underlying physical effect is the Edelstein effect that converts charge to angular momentum but the precise mechanism remains yet to be understood. Here, we introduce the minimal model for explaining the phenomenon based on the orbital Edelstein effect. We consider inter-site contributions to the current-induced orbital angular momentum and reveal the underlying mechanism by analytically calculating the Edelstein susceptibilities in a tight-binding and Boltzmann approach. While the orbital angular momentum is directly generated by the chirality of the crystal, the spin contribution of each spin-split band pair relies on spin-orbit coupling. Using tellurium as an example, we show that the orbital contribution surpasses the spin contribution by orders of magnitude.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
6 pages, 5 figures. This work was supported by the EIC Pathfinder OPEN grant 101129641 "Orbital Engineering for Innovative Electronics"
FF7: A Code Package for High-throughput Calculations and Constructing Materials Database
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Tiancheng Ma, Zihan Zhang, Shuting Wu, Defang Duan, Tian Cui
Decades accumulation of theory simulations lead to boom in material database, which combined with machine learning methods has been a valuable driver for the data-intensive material discovery, i.e., the fourth research paradigm. However, construction of segmented databases and data reuse in generic databases with uniform parameters still lack easy-to-use code tools. We herein develop a code package named FF7 (Fast Funnel with 7 modules) to provide command-line based interactive interface for performing customized high-throughput calculations and building your own handy databases. Data correlation studies and material property prediction can progress by built-in installation-free artificial neural network module and various post processing functions are also supported by auxiliary module. This paper shows the usage of FF7 code package and demonstrates its usefulness by example of database driven thermodynamic stability high-throughput calculation and machine learning model for predicting the superconducting critical temperature of clathrate hydrides.
Materials Science (cond-mat.mtrl-sci)
9 pages, 6 figures
Dipole-Mode Spectrum and Hydrodynamic Crossover in a Resonantly Interacting Two-Species Fermion Mixture
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-02-10 20:00 EST
Zhu-Xiong Ye, Alberto Canali, Chun-Kit Wong, Marian Kreyer, Emil Kirilov, Rudolf Grimm
Ultracold quantum-gas mixtures of fermionic atoms with resonant control of interactions offer a unique test-bed to explore few- and many-body quantum states with unconventional properties. The emergence of such strongly correlated systems, as for instance symmetry-broken superfluids, is usually accompanied by hydrodynamic collective behavior. Thus, experimental progress in this field naturally requires a deep understanding of hydrodynamic regimes. Here, we report on experiments employing a tunable Fermi-Fermi mixture of \(^{161}\)Dy and \(^{40}\)K near quantum degeneracy. We investigate the full spectrum of dipole modes across a Feshbach resonance and characterize the crossover from collisionless to deep hydrodynamic behavior in measurements of frequencies and damping rates. We compare our results with a theoretical model that considers the motion of the mass centers of the two species and we identify the contributions of friction and mean-field interaction. We show that one oscillating mode exists over the whole range of interactions, exhibiting striking changes of frequency and damping in the deep hydrodynamic regime. We observe the second oscillating mode to split into two purely exponential damping modes. One of these exponential modes shows very fast damping, faster than any other relevant timescale, and is largely insensitive against experimental imperfections. It provides an accurate measure for the interspecies drag effect, which generalizes the concept of spin drag explored in other experiments. We characterize the interspecies drag locally in terms of a microscopic friction coefficient and we discuss its unitarity-limited universal behavior on top of the resonance.
Quantum Gases (cond-mat.quant-gas)
20 pages, 11 figures
Unraveling effects of competing interactions and frustration in vdW ferromagnetic Fe3GeTe2 nanoflake devices
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Rajeswari Roy Chowdhury, Daiichi Kurebayashi, Jana Lustikova, Oleg A. Tretiakov, Shunsuke Fukami, Ravi Prakash Singh, Samik DuttaGupta
Two-dimensional (2D) van der Waals (vdW) magnets and devices have garnered significant attention owing to the stabilization of long range magnetic order down to atomic limit, and the prospect for novel quantum devices with unique functionalities. To achieve this objective, clarification of magnetotransport properties and understanding of the relevant interactions with lowering of dimensions are of extreme importance. Here, the magnetotransport properties of few atomic layer Fe3GeTe2 and (Co0.25Fe0.75)3GeTe2 nanoflake devices have been investigated. Magnetotransport investigations with applied magnetic field along the easy-axis shows anomalous Hall effect, while that for applied magnetic field along the hard-axis reveals an unusual behaviour. Atomistic calculations considering the presence of antiferromagnetic, ferromagnetic and local symmetry-breaking interactions reveal critical role of magnetic frustration effect assisted by thermal fluctuations, leading to a non-zero scalar spin chirality manifesting in an unconventional Hall effect. The present result clarifies the underlying interactions in few-layer 2D vdW ferromagnetic material system, important for the understanding of non-collinear spin configurations in vdW magnets for 2D spintronic devices.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
7 pages, 4 figures
Quantum anomalous Hall domains in a Quenched Topological Mott Insulator
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-02-10 20:00 EST
Lara Ulčakar, Gal Lemut, Tomaž Rejec, Jernej Mravlje
We study an interacting spinless quadratic band touching model that realizes a topological Mott insulating state. We quench the interaction from a value corresponding to the nematic insulator to that of the quantum anomalous Hall (QAH) ordered phase. We perform time-dependent Hartree-Fock simulations and show that after the quench the system realizes an excited Dirac semimetal state, which is however unstable and spontaneously evolves to a state with inhomogeneous nematic and QAH order parameters. The modulations form a stripe pattern that grows exponentially with time until the local Chern marker reaches unity. The alternating QAH order defines a domain structure with boundaries that host chiral sublattice currents.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
Comments are welcome
Energy dynamics in a class of local random matrix Hamiltonians
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-02-10 20:00 EST
Klée Pollock, Jonathan D. Kroth, Nathan Pagliaroli, Thomas Iadecola, Jonathan Riddell
Random matrix theory yields valuable insights into the universal features of quantum many-body chaotic systems. Although all-to-all interactions are traditionally studied, many interesting dynamical questions, such as transport of a conserved density, require a notion of spatially local interactions. We study the transport of the energy, the most basic conserved density, in few-body and 1D chains of nearest-neighbor random matrix terms that square to one. In the few-body but large local Hilbert space dimension case, we develop a mapping for the energy dynamics to a single-particle hopping picture. This allows for the computation of the energy density autocorrelators and an out-of-time-ordered correlator of the energy density. In the 1D chain, we numerically study the energy transport for a small local Hilbert space dimension. We also discuss the density of states throughout and touch upon the relation to free probability theory.
Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
18 pages, 9 figures
Two-Point Deterministic Equivalence for Stochastic Gradient Dynamics in Linear Models
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-02-10 20:00 EST
Alexander Atanasov, Blake Bordelon, Jacob A. Zavatone-Veth, Courtney Paquette, Cengiz Pehlevan
We derive a novel deterministic equivalence for the two-point function of a random matrix resolvent. Using this result, we give a unified derivation of the performance of a wide variety of high-dimensional linear models trained with stochastic gradient descent. This includes high-dimensional linear regression, kernel regression, and random feature models. Our results include previously known asymptotics as well as novel ones.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Machine Learning (cs.LG), Machine Learning (stat.ML)
Disentangling the Effects of Curvature and Misorientation on the Shrinkage Behavior of Loop-Shaped Grain Boundaries
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-02-10 20:00 EST
Fabrizio Camerin, Susana Marín-Aguilar, Tim Griffioen, Mathieu G. Baltussen, Roel P.A. Dullens, Berend van der Meer, Marjolein Dijkstra
The material properties of polycrystals are strongly affected by the evolution and coarsening of their internal grain structures. Yet, studying this process is challenging due to the complex interactions within grain boundary networks. Here, we systematically investigate the shrinkage of isolated loop-shaped grain boundaries in 2D colloidal crystals. Unexpectedly, we find that shear coupling decreases with increasing grain misorientation, contrary to geometric predictions. This counterintuitive result is attributed to enhanced concurrent sliding driven by the annihilation of dislocations. Furthermore, by focusing on the evolution of the grain size, we reveal a transition in shrinkage kinetics between small and large loop sizes, offering an explanation for previously observed discrepancies in grain boundary mobility. These findings reveal a more intricate dependence of grain boundary behavior on curvature and misorientation than previously reported, offering new insights into polycrystal coarsening dynamics.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech)
Fluctuation thermometry of an atom-resolved quantum gas: Beyond the fluctuation-dissipation theorem
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-02-10 20:00 EST
Maxime Dixmerias, Joris Verstraten, Cyprien Daix, Bruno Peaudecerf, Tim de Jongh, Tarik Yefsah
Thermometry is essential for studying many-body physics with ultracold atoms. Accurately measuring low temperatures in these systems, however, remains a significant challenge due to the absence of a universal thermometer. Most widely applicable methods, such as fitting of in-situ density profiles or standard fluctuation thermometry, are limited by the requirement of global thermal equilibrium and inapplicability to homogeneous systems. In this work, we introduce a novel in-situ thermometry for quantum gases, leveraging single-atom resolved measurements via quantum gas microscopy, and demonstrate it on an ideal Fermi gas. By analyzing number fluctuations in probe volumes with approximately one atom on average, we extract both global and local temperatures over a broad dynamic range. Unlike traditional fluctuation thermometry, our method does not rely on the fluctuation-dissipation theorem and is based instead on the exact relationship between number fluctuations and density-density correlations. In the low-temperature regime, it allows us to observe significant deviations from fluctuation-dissipation predictions, uncovering sub-extensive fluctuations. Our method is applicable to systems with arbitrary trapping potentials, requiring neither precise trap calibration nor global thermal equilibrium. This nearly universal thermometer for quantum gases overcomes key limitations of existing techniques, paving the way for more accurate and versatile temperature measurements in ultracold quantum systems.
Quantum Gases (cond-mat.quant-gas), Statistical Mechanics (cond-mat.stat-mech), Atomic Physics (physics.atom-ph), Quantum Physics (quant-ph)
11 pages, 7 figures
Revisiting ab-initio excited state forces from many-body Green's function formalism: approximations and benchmark
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-02-10 20:00 EST
Rafael R. Del Grande, David A. Strubbe
Ab initio techniques for studying the optical and vibrational properties of materials are well-established, but only a few recent studies have focused on the interaction between excitons and atomic vibrations. In this paper, we revisit the excited state forces method, which integrates results from GW/BSE and DFPT calculations to determine the gradient of the excited state energy. We explore its technical aspects, including convergence and the quality of approximations used. We successfully apply this method to investigate self-trapped excitons in LiF. The excited state forces method provides valuable insights into ionic dynamics in the excited state and the microscopic mechanism of exciton self-trapping.
Materials Science (cond-mat.mtrl-sci)
Stirring supercooled colloidal liquids at the particle scale
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-02-10 20:00 EST
We study the decay of tangential velocity profiles with distance from a local disturbance in hard-sphere colloidal suspensions as the colloidal glass transition is approached. The disturbance, generated by a dimer of superparamagnetic particles rotated by an external magnetic field, enables a precise characterization of the system's response through confocal microscopy and tracking of individual particle dynamics. The tangential velocity profiles exhibit nearly exponential decay with distance. As particle density increases toward the colloidal glass transition, the characteristic length scale derived from exponential fits grows. We also observe that the colloidal particles slip against the rotating dimer, with less slip in samples which are closer to the glass transition.
Soft Condensed Matter (cond-mat.soft)
8 pages, 6 figures
Observation of a dynamic magneto-chiral instability in photoexcited tellurium
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-02-10 20:00 EST
Yijing Huang, Nick Abboud, Yinchuan Lv, Penghao Zhu, Azel Murzabekova, Changjun Lee, Emma A. Pappas, Dominic Petruzzi, Jason Y. Yan, Dipanjan Chauduri, Peter Abbamonte, Daniel P. Shoemaker, Rafael M. Fernandes, Jorge Noronha, Fahad Mahmood
In a system of charged chiral fermions driven out of equilibrium, an electric current parallel to the magnetic field can generate a dynamic instability by which electromagnetic waves become amplified. Whether a similar instability can occur in chiral solid-state systems remains an open question. Using time-domain terahertz (THz) emission spectroscopy, we detect signatures of what we dub a ``dynamic magneto-chiral instability" in elemental tellurium, a structurally chiral crystal. Upon transient photoexcitation in a moderate external magnetic field, tellurium emits THz radiation consisting of coherent modes that amplify over time. An explanation for this amplification is proposed using a theoretical model based on a dynamic instability of electromagnetic waves interacting with infrared-active oscillators of impurity acceptor states in tellurium to form an amplifying polariton. Our work not only uncovers the presence of a magneto-chiral instability but also highlights its promise for THz-wave amplification in chiral materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech)
Supplementary Information (SI) available as a PDF in the TeX source