CMP Journal 2025-06-16
Statistics
Nature: 1
Nature Nanotechnology: 2
Nature Physics: 1
Nature Reviews Materials: 1
arXiv: 48
Nature
Cryo-EM structure of a natural RNA nanocage
Original Paper | Cryoelectron microscopy | 2025-06-15 20:00 EDT
Xiaobin Ling, Dmitrij Golovenko, Jianhua Gan, Jinbiao Ma, Andrei A. Korostelev, Wenwen Fang
Long (>200 nucleotides) non-coding RNAs (lncRNAs) play important roles in diverse aspects of life. Over 20 classes of lncRNAs have been identified in bacteria and bacteriophages through comparative genomics analyses, but their biological functions remain largely unexplored1-3. Due to the large sizes, the structural determinants of most lncRNAs also remain uncharacterized. Here we report the structures of two natural RNA nanocages formed by the lncRNA ROOL (rumen-originating, ornate, large) found in bacterial and phage genomes. ~2.9 Å cryo-electron microscopy (cryo-EM) structures reveal that ROOL RNAs form an octameric nanocage with a 28-nm diameter and 20-nm axial length, whose hollow inside features poorly ordered regions. The octamer is stabilized by numerous tertiary and quaternary interactions, including triple-strand A-minors that we propose to name “A-minor staples”. The structure of an isolated ROOL monomer at ~3.2-Å resolution indicates that nanocage assembly involves a strand-swapping mechanism resulting in quaternary kissing loops. Finally, we show that ROOL RNA fused to an RNA aptamer, tRNA, or microRNA retains its structure forming a nanocage with radially displayed cargos. Our findings therefore may enable the engineering of novel RNA nanocages as delivery vehicles for research and therapeutic applications.
Cryoelectron microscopy, Nanostructures
Nature Nanotechnology
Nanoneedles enable spatiotemporal lipidomics of living tissues
Original Paper | Diagnostic devices | 2025-06-15 20:00 EDT
Chenlei Gu, Davide Alessandro Martella, Leor Ariel Rose, Nadia Rouatbi, Cong Wang, Alaa Zam, Valeria Caprettini, Magnus Jensen, Shiyue Liu, Cathleen Hagemann, Siham Memdouh, Andrea Serio, Vincenzo Abbate, Khuloud T. Al-Jamal, Maddy Parsons, Mads S. Bergholt, Paul M. Brennan, Assaf Zaritsky, Ciro Chiappini
Spatial biology provides high-content diagnostic information by mapping the molecular composition of tissues. However, traditional spatial biology approaches typically require non-living samples, limiting temporal analysis. Here, to address this limitation, we present a workflow using porous silicon nanoneedles to repeatedly collect biomolecules from live brain tissues and map lipid distribution through desorption electrospray ionization mass spectrometry imaging. This method preserves the integrity of the original tissue while replicating its spatial molecular profile on the nanoneedle substrate, accurately reflecting lipid distribution and tissue morphology. Machine learning analysis of 23 human glioma biopsies demonstrated that nanoneedle sampling enables the precise classification of disease states. Furthermore, a spatiotemporal analysis of mouse gliomas treated with temozolomide revealed time- and treatment-dependent variations in lipid composition. Our approach enables non-destructive spatiotemporal lipidomics, advancing molecular diagnostics for precision medicine.
Diagnostic devices, Nanobiotechnology
A nanovaccine targeting cancer stem cells and bulk cancer cells for postoperative cancer immunotherapy
Original Paper | Drug delivery | 2025-06-15 20:00 EDT
Qing You, Gege Wu, Hui Li, Jingyi Liu, Fangfang Cao, Lingwen Ding, Fuming Liang, Bo Zhou, Lilusi Ma, Ling Zhu, Chen Wang, Yanlian Yang, Xiaoyuan Chen
Residual cancer stem-like cells (CSCs) can cause tumour recurrence within a narrow margin around the initial tumour resection lesion, increasing the risk of post-surgical relapse and incurability. Currently, there are no efficient strategies for tracking and eradicating CSCs. Here we propose a nanovaccine strategy, called NICER, based on a nanovesicle system integrating CSC-specific antigen display and epigenetic nano-regulator encapsulation with a dendritic-cell-targeting aptamer, to simultaneously eradicate CSCs and bulk tumour cells. Specifically, nanovesicles derived from aldehyde-dehydrogenase-overexpressing tumours could serve as integrated antigens carrying both CSC-specific antigen and tumour-associated antigen. Epigenetic nano-regulator targeting YTH N6-methyladenosine RNA binding protein 1 could restrict dendritic cell lysosomal protease activity to modulate the effective cross-presentation of integrated antigens via major histocompatibility complex class I for immune responses. Overall, NICER represents a broad-spectrum vaccine approach against both CSCs and bulk tumours that can significantly inhibit postoperative cancer recurrence and metastasis, prolonging survival rates.
Drug delivery, Nanotechnology in cancer
Nature Physics
Experimental demonstration of breakeven for a compact fermionic encoding
Original Paper | Quantum information | 2025-06-15 20:00 EDT
Ramil Nigmatullin, Kévin Hémery, Khaldoon Ghanem, Steven Moses, Dan Gresh, Peter Siegfried, Michael Mills, Thomas Gatterman, Nathan Hewitt, Etienne Granet, Henrik Dreyer
Solving the Fermi-Hubbard model is a central task in the study of strongly correlated materials. Digital quantum computers can, in principle, be suitable for this purpose, but have so far been limited to quasi-one-dimensional models. This is because of exponential overheads caused by the interplay of noise and the non-locality of the mapping between fermions and qubits. Here we use a trapped-ion quantum computer to experimentally demonstrate that a recently developed local encoding can overcome this problem. In particular, we show that suitable reordering of terms and application of circuit identities–a scheme called corner hopping–substantially reduces the cost of simulating fermionic hopping. This enables the efficient preparation of the ground state of a 6 × 6 spinless Fermi-Hubbard model encoded in 48 physical qubits. We also develop two error mitigation schemes for systems with conserved quantities, based on local postselection and on extrapolation of local observables, respectively. Our results suggest that Fermi-Hubbard models beyond classical simulability can be addressed by digital quantum computers without large increases in gate fidelity.
Quantum information, Quantum simulation
Nature Reviews Materials
Overcoming copper stability challenges in CO2 electrolysis
Review Paper | Electrocatalysis | 2025-06-15 20:00 EDT
Jesse Kok, Petru P. Albertini, Jari Leemans, Raffaella Buonsanti, Thomas Burdyny
Copper and copper-based catalysts can electrochemically convert CO2 into ethylene and higher alcohols, among other products, at room temperature and pressure. This approach may be suitable for the production of high-value compounds. However, such a promising reaction is heavily burdened by the instability of copper during CO2 reduction. To date, non-copper catalysts have also failed to supplant the activity and selectivity of copper, leaving CO2-to-C2 electrolysis in the balance. In this Perspective, we discuss copper catalyst instability from both the atomistic and the microstructure viewpoint. We motivate that increased fundamental understanding, material design and operational approaches, along with increased reporting of failure mechanisms, will contribute to overcoming the barriers to multi-year operation. Our narrative focuses on the copper catalyst reconstruction occurring during CO2 reduction as one of the major causes inducing loss of C2 activity. We conclude with a rational path forward towards longer operations of CO2-to-C2 electrolysis.
Electrocatalysis, Electrochemistry, Surface chemistry
arXiv
Charge Modulation in the Vortex Halo of a Superconductor Enhances its Critical Magnetic Field
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-16 20:00 EDT
Anurag Banerjee, Catherine Pépin, Nandini Trivedi, Amit Ghosal
When an orbital magnetic field suppresses superconductivity, forming periodic vortices in type-II superconductors, subdominant orders can emerge in the vortex cores. Rather than competing with superconductivity, we find that the emergent charge order within the halo of a vortex makes superconductivity more robust by enhancing the upper critical field. We establish that charge modulations nucleate in and around the vortex core for model parameters dictated by the underlying non-superconducting state. We further show that the spectral signatures from the Caroli-de Gennes-Matricon (CdGM) bound states in vortex cores track the charge modulation. The CdGM-like peak is found to shift toward the gap edge and oscillate from particle-to-hole bias from site to site, signaling charge modulation.
Superconductivity (cond-mat.supr-con)
6 pages with 4 pages additional material
Mechanism and Stability of Li-Dynamics in Amorphous Li-Ti-P-S Based Mixed Ionic-Electronic Conductor
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Selva Chandrasekaran Selvaraj, Daiwei Wang, Donghai Wang, Anh T. Ngo
Mixed ionic-electronic conductor (MIEC) exhibit both high ionic and electronic conductivity to improve the battery performance. In this work, we investigate the mechanism and stability of transport channels in recently developed our MIEC material, amorphous Ti-doped lithium phosphorus sulfide (LPS), using molecular dynamics (MD) simulations with a 99% accurate machine-learning force field (MLFF) trained on \textit{ab-initio} MD data. The achieved MLFF helps efficient large-scale MD simulations on LPS with three Ti concentrations (10%, 20%, and 30%) and six temperatures (25$ ^\mathrm{o}$ C to 225$ ^\mathrm{o}$ C) to calculate ionic conductivity, activation energy, Li-ion transport mechanism, and configurational entropy. Results show that ionic conductivities and activation energies are consistent with our recent experimental values. Moreover, Li-ion transport occurs via free-volume diffusion facilitated by the formation of disordered Li-S polyhedra. Enhanced stability of transport channels at 10% and 20% Ti doping, compared to 0% and 30%, is observed through the analysis of the vibrational and configurational entropy of these disordered Li-S polyhedra. Overall, this study highlights the utility of MLFF-based large-scale MD simulations in explaining the transport mechanism and its stability of Li-ion in Ti doped LPS electrolyte with significant computational efficiency.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
7 figures and 14 pages
Anyon dispersion from non-uniform magnetic field on the sphere
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-16 20:00 EDT
Mina-Lou Schleith, Tomohiro Soejima, Eslam Khalaf
The discovery of fractional quantum anomalous Hall states in moiré systems has raised the interesting possibility of realizing phases of itenerant anyons. Anyon dispersion is only possible in the absence of continuous magnetic translation symmetry (CMTS). Motivated by this, we consider anyons on the sphere in the presence of a non-uniform magnetic field which breaks the $ {\rm SU}(2)$ rotation symmetry, the analog of CMTS on the sphere, down to a $ {\rm U}(1)$ . This allows us to study the energy dispersion of the anyons as a function of $ L_z$ angular-momentum, while maintaining the perfect flatness of single-particle dispersion. Parametrizing the non-uniform field by a real parameter $ R$ which concentrates the field at the north (south) pole for $ R>1$ ($ R < 1$ ), we use exact diagonalization to verify nonzero energy-angular momentum dispersion for any $ R \neq 1$ . For our choice of non-uniform field, we show that any $ p$ -body correlation function evaluated in the space of Laughlin quasiholes for any value of $ R$ can be mapped exactly to a corresponding $ p$ -body correlation function in uniform field. In the thermodynamic limit, this enables us to analytically compute the interaction-generated spatially varying potential felt by the anyons and the resulting anyon dispersion exactly, up to an overall scaling constant, for the cases of short-range and Coulomb interaction. The anyon dispersion in our model describes azimuthal motion around the sphere at a constant height, similar to spin precession. Our work therefore serves as a concrete demonstration that interaction alone can generate nonzero anyon dispersion in the presence of inhomogeneous magnetic field.
Strongly Correlated Electrons (cond-mat.str-el)
5 pages, 3 figure
Origins of chalcogenide perovskite instability
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Adelina Carr, Talia Glinberg, Nathan Stull, James R. Neilson, Christopher J. Bartel
Chalcogenide perovskites, particularly II-IV ABS3 compounds, are a promising class of materials for optoelectronic applications. However, these materials frequently exhibit instability in two respects: 1) a preference for structures containing one-dimensional edge- or face-sharing octahedral networks instead of the three-dimensional corner-sharing perovskite framework (polymorphic instability), and (2) a tendency to decompose into competing compositions (hull instability). We evaluate the stability of 81 ABS3 compounds using Density Functional Theory, finding that only BaZrS3 and BaHfS3 are both polymorphically and hull stable, with the NH4CdCl3-type structure the preferred polymorph for 77% of these compounds. Comparison with existing tolerance factor models demonstrates that these approaches work well for known perovskites but overpredict stability for compositions without published experimental results. Polymorphic stability analysis reveals that perovskite structures are stabilized by strong B-S bonding interactions, while needle structures exhibit minimal B-S covalency, suggesting that electrostatic rather than covalent interactions drive the preference for edge-sharing motifs. Hull stability analysis comparing ABS3 to ABO3 analogues reveals a weaker inductive effect in sulfides as a possible explanation for the scarcity of sulfides compared with oxides. The relative instability of ABS3 compounds is further supported by experimental synthesis attempts. These findings provide fundamental insights into the origins of instability in chalcogenide perovskites and highlight the challenges in expanding this promising materials class beyond the few materials that have been reported to date.
Materials Science (cond-mat.mtrl-sci)
Optimized Gutzwiller Projected States for Doped Antiferromagnets in Fermi-Hubbard Simulators
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-16 20:00 EDT
Christian Reinmoser, Muqing Xu, Lev Haldar Kendrick, Anant Kale, Youqi Gang, Martin Lebrat, Markus Greiner, Fabian Grusdt, Annabelle Bohrdt
In quantum many-body physics, one aims to understand emergent phenomena and effects of strong interactions, ideally by developing a simple theoretical picture. Recently, progress in quantum simulators has enabled the measurement of site resolved snapshots of Fermi-Hubbard systems at finite doping on square as well as triangular lattice geometries. These experimental advances pose the quest for theorists to analyze the ensuing data in order to gain insights into these prototypical, strongly correlated many-body systems. Here we employ machine learning techniques to optimize the mean-field parameters of a resonating valence bond (RVB) state through comparison with experimental data, thus determining a possible underlying simple model that is physically motivated and fully interpretable. We find that the resulting RVB states are capable of capturing two- as well as three-point correlations measured in experiments, even when they are not specifically used in the optimization. The analysis of the mean-field parameters and their doping dependence can be used to obtain physical insights and shed light on the nature of possible underlying quantum spin liquid states. Our results show that finite temperature data from Fermi-Hubbard quantum simulators can be well captured by RVB states. This work paves the way for a new, systematic analysis of data from numerical as well as quantum simulation of strongly correlated quantum many-body systems.
Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 7 figures
Stripe order in quasicrystals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-16 20:00 EDT
Rafael M. P. Teixeira, Eric C. Andrade
We explore the emergence of magnetic order in geometrically frustrated quasiperiodic systems, focusing on the interplay between local tile symmetry and frustration-induced constraints. In particular, we study the $ J_1$ -$ J_2$ Ising model on the two-dimensional Ammann-Beenker quasicrystal. Through large-scale Monte Carlo simulations and general arguments, we map the phase diagram of the model. For small $ J_2$ , a Néel phase appears, whereas a stripe phase is stable for dominant antiferromagnetic $ J_2$ , despite the system’s lack of periodicity. Although long-range stripe order emerges below a critical temperature, unlike in random systems, it is softened by the nucleation of competing stripe domains pinned at specific quasiperiodic sites. This behavior reveals a unique mechanism of symmetry breaking in quasiperiodic lattices, where geometric frustration and local environment effects compete to determine the magnetic ground state. Our results show how long-range order adapts to non-periodic structures, with implications for understanding nematic phases and other broken-symmetry states in quasicrystals.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech)
7 pages, 8 figures. Contribution to the EPJB topical issue Phase Transitions and Magnetism in Spin Systems
Full distribution of the number of distinct sites visited by a random walker in dimension $d \ge 2$
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
We study the full distribution $ P_M(S)$ of the number of distinct sites $ S$ visited by a random walker on a $ d$ -dimensional lattice after $ M$ steps. We focus on the case $ d \ge 2$ , and we are interested in the long-time limit $ M \gg 1$ . Our primary interest is the behavior of the right and left tails of $ P_M(S)$ , corresponding to $ S$ larger and smaller than its mean value, respectively. We present theoretical arguments that predict that in the right tail, a standard large-deviation principle (LDP) $ P_{M}\left(S\right)\sim e^{-M\Phi\left(S/M\right)}$ is satisfied (at $ M \gg 1$ ) for $ d\ge2$ , while in the left tail, the scaling behavior is $ P_{M}\left(S\right)\sim e^{-M^{1-2/d}\Psi\left(S/M\right)}$ , corresponding to a LDP with anomalous scaling, for $ d>2$ . We also obtain bounds for the scaling functions $ \Phi(a)$ and $ \Psi(a)$ , and obtain analytical results for $ \Phi(a)$ in the high-dimensional limit $ d \gg 1$ , and for $ \Psi(a)$ in the limit $ a \ll 1$ (describing the far left tail). Our predictions are validated by numerical simulations using importance sampling algorithms.
Statistical Mechanics (cond-mat.stat-mech), Probability (math.PR)
8 pages, 3 figures
Information thermodynamics of cellular ion pumps
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Julian D. Jiménez-Paz, Matthew P. Leighton, David A. Sivak
The framework of bipartite stochastic thermodynamics is a powerful tool to analyze a composite system’s internal thermodynamics. It has been used to study the components of different molecular machines such as ATP synthase. However, this approach has not yet been used to describe ion-transporting proteins despite their high-level functional similarity. Here we study the bipartite thermodynamics of the sodium-potassium pump in the nonequilibrium steady state. Using a physically intuitive partition between the ATP-consuming subsystem and the ion-transporting subsystem, we find considerable information flow comparable to other molecular machines, and Maxwell-demon behavior in the ATP-consuming subsystem. We vary ion concentrations and transmembrane voltage in a range including the neuronal action potential, and find that the information flow inverts during depolarization.
Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph)
9 pages, 5 figures
Tunable Photodetectors Based on 2D Hybrid Structures from Transition Metal Dichalcogenides and Photochromic Molecules
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Sewon Park, Jaehoon Ji, Joakim Andreasson, Jeong Ho You, Jong Hyun Choi
This article reviews recent progress in two-dimensional (2D) hybrid structures that integrate transition metal dichalcogenides (TMDs) with photochromic molecules for photodetector applications. Atomically thin TMD semiconductors offer strong light-matter interaction, tunable bandgaps, and efficient carrier transport, making them suitable for photodetectors. Photochromic molecules, capable of reversible structural changes in response to external light, can modulate their chemical, optical, and electronic properties. The combinations of various light-adaptive compounds and TMDs provide a versatile platform to explore optically programmable behaviors such as wavelength-selective photoresponse, nonvolatile switching, and multilevel memory characteristics. TMD/photochromic hybrids offer new functional capabilities that are difficult to achieve with either component alone. This mini-review summarizes material properties, interfacial integration strategies, working mechanisms, and representative device demonstrations. We conclude by highlighting future research directions toward the practical implementation of photoresponsive hybrid systems in high-performance adaptive optoelectronics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
26 pages, 5 figures, 1 table
Antichiral edge states and Bogoliubov Fermi surfaces in a two-dimensional proximity-induced superconductor
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Gabriel F. Rodríguez Ruiz, Juan Herrera-Mateos, Leandro Tosi, Christoph Strunk, Carlos Balseiro, Liliana Arrachea
We show that a magnetic field parallel to the plane of a two-dimensional electron gas with Rashba spin orbit coupling in proximity to a superconductor leads to a topological phase in coexistence with a single pair of Bogoliubov Fermi surfaces. This phase hosts antichiral edge states of co-propagating Majorana fermions and are spatially localized at the opposite edges of the sample, perpendicular to the magnetic field. We discuss the characteristic signatures in the current-phase relation of a Josephson junction formed by two reservoirs in the topological phase.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
Theory of infrared magneto-optical effects from chiral phonons in solids
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Chiara Fiorazzo, Cheol-Hwan Park, Ivo Souza, Matteo Calandra
In crystals with broken time-reversal symmetry, zone-center phonons can acquire a finite angular momentum via velocity-dependent forces on the nuclei. Despite having the same order of magnitude as the electron spin angular momentum, the phonon angular momentum can be hard to detect because the frequency splitting is small. Here, by developing a theory of lattice magneto-optical effects in reflection and transmission, we show that infrared magnetic circular dichroism is a sensitive probe of zone-center phonon chirality. We evaluate the infrared magneto-optical Faraday, Kerr, and circular-dichroism spectra of CrI$ _3$ from time-dependent density-functional theory in the adiabatic local-density approximation. We find sizeable circular dichroism from the infrared-active E$ _u$ mode at $ \approx 214$ cm$ ^{-1}$ , even though the calculated splitting is only 0.22 cm$ ^{-1}$ .
Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other)
11 pages, 9 pictures
Bulk Excitations of Invertible Phases
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-16 20:00 EDT
Wenjie Ji, David T. Stephen, Michael Levin, Xie Chen
Recent developments in the study of topological defects highlight the importance of understanding the multi-dimensional structure of bulk excitations inside a quantum system. When the bulk ground state is trivial, i.e. a product state, excitations on top of it are decoupled from each other and correspond to lower-dimensional phases and their defects within. In this paper, we expand the discussion to invertible phases and study the bulk excitations in, for example, SPT phases, Majorana chains, p + ip superconductors etc. We find that there is a one-to-one correspondence between bulk excitations inside a nontrivial invertible phase and those in a product state. For SPT phases, this can be shown using the symmetric Quantum Cellular Automaton that maps from the product state to the SPT state. More generally, for invertible phases realizable using the Topological Holography construction, we demonstrate the correspondence using the fact that certain gapped boundary conditions of a topological bulk state have only relative distinctions but no absolute ones.
Strongly Correlated Electrons (cond-mat.str-el)
41 pages, 27 figures
Polymorphism Crystal Structure Prediction with Adaptive Space Group Diversity Control
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Sadman Sadeed Omee, Lai Wei, Sourin Dey, Jianjun Hu
Crystalline materials can form different structural arrangements (i.e. polymorphs) with the same chemical composition, exhibiting distinct physical properties depending on how they were synthesized or the conditions under which they operate. For example, carbon can exist as graphite (soft, conductive) or diamond (hard, insulating). Computational methods that can predict these polymorphs are vital in materials science, which help understand stability relationships, guide synthesis efforts, and discover new materials with desired properties without extensive trial-and-error experimentation. However, effective crystal structure prediction (CSP) algorithms for inorganic polymorph structures remain limited. We propose ParetoCSP2, a multi-objective genetic algorithm for polymorphism CSP that incorporates an adaptive space group diversity control technique, preventing over-representation of any single space group in the population guided by a neural network interatomic potential. Using an improved population initialization method and performing iterative structure relaxation, ParetoCSP2 not only alleviates premature convergence but also achieves improved convergence speed. Our results show that ParetoCSP2 achieves excellent performance in polymorphism prediction, including a nearly perfect space group and structural similarity accuracy for formulas with two polymorphs but with the same number of unit cell atoms. Evaluated on a benchmark dataset, it outperforms baseline algorithms by factors of 2.46-8.62 for these accuracies and improves by 44.8%-87.04% across key performance metrics for regular CSP. Our source code is freely available at this https URL.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
The Integral Decimation Method for Quantum Dynamics and Statistical Mechanics
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Ryan T. Grimm, Alexander J. Staat, Joel D. Eaves
We present a method to numerically evaluate functional integrals called integral decimation (ID). It constructs a separable decomposition of the integrand as a spectral tensor train (STT), a continuous generalization of the matrix product state. ID builds the STT by mapping the integrand to an auxiliary many-body wavefunction that evolves in time from an initially unentangled state. Each body-ordered term of the action corresponds to a quantum gate, applied to the state during its evolution. The gates generate entanglement, and decimation during the gate sequence compresses the integral, alleviating memory bottlenecks in high dimensional integration. In the application of ID to moment-generating and partition functions, the continuous nature of the STTs allows for analytical differentiation of the result. To demonstrate its versatility, we employ ID to calculate the partition function of a classical XY model and to solve a non-Markovian quantum relaxation problem. By circumventing the barren plateau problem that limited our earlier STT-based approaches to quantum relaxation [J. Chem. Phys. 161, 234111 (2024)], ID enables high-accuracy simulations of quantum dynamics in systems as large as a 40-site chain.
Statistical Mechanics (cond-mat.stat-mech), Chemical Physics (physics.chem-ph), Computational Physics (physics.comp-ph), Quantum Physics (quant-ph)
12 pages, 7 figures
Semi-empirical Pseudopotential Method for Monolayer Transitional-Metal Dichalcogenides
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Raj Kumar Paudel, Chung-Yuan Ren, Yia-Chung Chang
We present a Semiempirical Pseudopotential Method for accurately computing the band structures and Bloch states of monolayer transition-metal dichalcogenides (TMDCs), including MoS2, MoSe2, WS2, and WSe2. Our approach combines local and non-local pseudopotentials, carefully fitted to replicate fully self-consistent density-functional theory results, while using only a minimal set of empirical parameters. By expressing the total potential as a sum of a few separable components, we achieve both accuracy and computational efficiency. The resulting pseudopotentials are transferable to more complex systems such as bilayer, trilayer, and moire superlattices, offering a reliable foundation for large-scale simulations. When integrated with artificial intelligence techniques, this method provides a powerful tool for the design and exploration of TMDC-based nanodevices for next-generation optoelectronic applications.
Materials Science (cond-mat.mtrl-sci)
14 pages, 8 figures
In-Plane Ni-O-Ni Bond Angles as Structural Fingerprints of Superconductivity in Layered Nickelates: Effects of Pressure, Strain, Layering, and Correlations
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-16 20:00 EDT
Bipasa Samanta, Alexandru B. Georgescu
We investigate the structural and electronic conditions conducive to superconductivity in layered nickelates using density functional theory with Hubbard corrections (DFT+$ U$ ). For both the bilayer and 1-3 polymorphs of La$ _3$ Ni$ _2$ O$ _7$ , we find that the in-plane Ni-O-Ni bond angles under pressure strongly correlate with the experimentally observed superconducting transition temperature ($ T_c$ ) dome, and may serve as a reasonable proxy. Under compressive strain, the bond angles straighten, peaking near 2% strain-consistent with experimental reports of superconductivity in strained bilayer thin films. However, the bond angles at this strain are more bent than those achieved under hydrostatic pressure, correlating with a lower $ T_c$ . We show that increasing the number of NiO$ _2$ layers, as in La$ _4$ Ni$ _3$ O$ _{10}$ , or substituting heavier rare-earth elements (e.g., Pr) raises the pressure required to reach the structural configuration associated with superconductivity. Our results indicate that these systems require higher external pressure to achieve in-plane bond straightening. Varying the on-site Coulomb interaction $ U$ reveals that stronger electronic correlations delay the structural transition and favor high-spin states. This suggests that moderate correlation strength may be optimal for superconductivity, with stronger correlation preventing the formation of favorable bond geometries. Electronic structure analysis shows that the Ni $ e_g$ orbitals dominate near the Fermi level and shift downward with pressure, enhancing Ni-O hybridization. These results highlight how pressure and strain tune structural features that may be essential for engineering high-$ T_c$ phases in nickelate superconductors.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
Compressed self-avoiding walks in two and three dimensions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
C J Bradly, N R Beaton, A L Owczarek
We consider the phase transition induced by compressing a self-avoiding walk in a slab where the walk is attached to both walls of the slab in two and three dimensions, and the resulting phase once the polymer is compressed. The process of moving between a stretched situation where the walls pull apart to a compressed scenario is a phase transition with some similarities to that induced by pulling and pushing the end of the polymer. However, there are key differences in that the compressed state is expected to behave like a lower dimensional system, which is not the case when the force pushes only on the endpoint of the polymer. We use scaling arguments to predict the exponents both of those associated with the phase transition and those in the compressed state and find good agreement with Monte Carlo simulations.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
8 pages, 5 figures
Three-dimensional topological orbital Hall effect caused by magnetic hopfions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Magnetic hopfions are non-collinear spin textures that are characterized by an integer topological invariant, called Hopf index. The three-dimensional magnetic solitons can be thought of as a tube with a twisted magnetization that has been closed at both ends to form a torus. The tube consists of a magnetic whirl called in-plane skyrmion or bimeron. Although hopfions have been observed by microscopy techniques, their detection remains challenging as they lack an electronic hallmark so far. Here we predict a three-dimensional orbital Hall effect caused by hopfion textures: When an electric field is applied, the hopfion generates a transverse current of orbital angular momentum. The effect arises due to the local emergent field that gives rise to in-plane and out-of-plane orbital Hall conductivities. This orbital Hall response can be seen as a hallmark of hopfions and allows us to distinguish them from other textures, like skyrmioniums, that look similar in real-space microscopy experiments. While the two-dimensional topological invariant of a skyrmion determines its topological Hall transport, the unique three-dimensional topological orbital Hall effect can be identified with the three-dimensional topological invariant that is the Hopf index. Our results make hopfions attractive for spin-orbitronic applications because their orbital signatures allow for their detection in devices and give rise to large orbital torques.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
12 pages, 7 figures. This work was supported by the EIC Pathfinder OPEN grant 101129641 Orbital Engineering for Innovative Electronics
Universal Scaling Laws for Deep Indentation Beyond the Hertzian Regime
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-16 20:00 EDT
Tong Mu, Changhong Linghu, Yanju Liu, Jinsong Leng, Huajian Gao, K. Jimmy Hsia
Deep indentation of soft materials is ubiquitous across scales in nature and engineering, yet accurate predictions of contact behaviors under extreme deformations ($ \delta/R > 1$ ) remain elusive due to geometric and material nonlinearities. Here, we investigate the indentation of rigid spheres into soft elastic substrates, resolving the highly nonlinear regime where the sphere becomes fully submerged. A universal geometric mapping approach reveals Hertz-type pressure distributions in the deformed configuration, validated by FEA. Closed-form solutions for contact force and radius agree with simulations up to $ \delta/R = 2.5$ . Experiments spanning soft polymers (Ecoflex, PDMS), food substrates (tofu), and biological tissues (octopus) validate the derived scaling law for hyperelastic materials. Our results establish a universal framework for extreme mechanical interactions, with applications in soft robotics, bioengineered systems, and tissue mechanics.
Soft Condensed Matter (cond-mat.soft)
Approach to network failure due to intrinsic fluctuations
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Shaunak Roy, Vimal Kishore, M. S. Santhanam
A networked system can fail when most of its components are unable to support flux through the nodes and edges. As studied earlier this scenario can be triggered by an external perturbation such as an intentional attack on nodes or for internal reasons such as due to malfunction of nodes. In either case, the asymptotic failure of the network is preceded by a cascade of nodal failures. In this work, we focus on the nodal failure arising from the intrinsic fluctuations in the flux passing through the nodes. By modeling these as extreme events, it is shown that three distinct nodal failure regimes can be identified before a complete network failure takes place. Further, the approach to network failure through the three regimes is shown to be qualitatively similar on a square lattice, all-to-all, scale free, and Erdos-Renyi networks. We obtain approximate analytical description of the approach to failure for an all-to-all network. This is also demonstrated numerically for real transportation network of flights.
Statistical Mechanics (cond-mat.stat-mech)
8 pages, 12 figures
Uni-Traveling-Carrier Photodiode Based on MoS2/GaN van der Waals Heterojunction for High-Speed Visible-Light Detection
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Takuya Kadowaki, Takahiro Serikawa, Akihide Ichikawa, Yuji Ohmaki, Koji Usami, Yoichi Kawakami, Yoshihiro Iwasa, Hisashi Ogawa
Uni-traveling-carrier photodiodes (UTC-PDs), which utilize only electrons as the active carriers, have become indispensable in high-speed optoelectronics due to their unique capabilities, such as high saturation power and broad bandwidth. However, extending the operating wavelengths into the visible region for wider applications is challenging due to the lack of suitable wide-bandgap III-V semiconductor combinations with the necessary band alignment and lattice matching. Here, we show that a UTC-PD based on a van der Waals heterojunction composed of a 2D transition metal dichalcogenide, molybdenum disulfide (MoS2), as a photoabsorption layer and a gallium nitride (GaN) film as a carrier transport layer, offers a solution to this challenge. The fast vertical carrier transport across the heterointerface is enabled by the direct epitaxial growth of a MoS2 layer on a GaN film. Our device demonstrates a frequency response in the several-GHz range with a quantum efficiency on the order of 1% throughout the entire visible spectrum, highlighting the promise for high-speed visible optoelectronics.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Topologically nontrivial and trivial flat bands via weak and strong interlayer coupling in twisted bilayer honeycomb optical lattices for ultracold atoms
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-16 20:00 EDT
Wenjie Sui, Wei Han, Zheng Vitto Han, Zengming Meng, Jing Zhang
In recent years, flat electronic bands in twisted bilayer graphene (TBG) have attracted significant attention due to their intriguing topological properties, extremely slow electron velocities, and enhanced density of states. Extending twisted bilayer systems to new configurations is highly desirable, as it offers promising opportunities to explore flat bands beyond TBG. Here, we study both topological and trivial flat bands in a twisted bilayer honeycomb lattice for ultracold atoms and present the evolution of the flat bands with different interlayer coupling strength (ICS). Our results demonstrate that an isolated topological flat band can emerge at the Dirac point energy for a specific value of weak ICS, referred to as the ``critical coupling”. This occurs over a wide range of twist angles, surpassing the limits of the magic angle in TBG systems. When the ICS is slightly increased beyond the critical coupling value, the topological flat band exhibits degenerate band crossings with both the upper and lower adjacent bands at the high-symmetry $ \Gamma_s$ point. As the ICS is further increased into the strong coupling regime, trivial flat bands arise around Dirac point energy. Meanwhile, more trivial flat bands appear, extending from the lowest to higher energy bands, and remain flat as the ICS increases. The topological properties of the flat bands are studied through the winding pattern of the Wilson loop spectrum. Our research provides deeper insights into the formation of flat bands in ultracold atoms with highly controllable twisted bilayer optical lattices, and may contribute to the discovery of new strongly correlated states of matter.
Quantum Gases (cond-mat.quant-gas)
Phys. Rev. A 111, 063306 (2025)
Magnon-magnon interaction induced by nonlinear spin wave dynamics
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Matteo Arfini, Alvaro Bermejillo-Seco, Artem Bondarenko, Clinton A. Potts, Yaroslav M. Blanter, Herre S. J. van der Zant, Gary A. Steele
We experimentally and theoretically demonstrate that nonlinear spin-wave dynamics can induce an effective resonant interaction between non-resonant magnon modes in a yttrium iron garnet disk. Under strong pumping near the ferromagnetic resonance mode, we observe a spectral splitting that emerges with increasing drive amplitude. This phenomenon is well captured by a theoretical framework based on the linearization of a magnon three-wave mixing Hamiltonian, which at high power leads to parametric Suhl instabilities. The access and control of nonlinear magnon-parametric processes enables the development of experimental platforms in an unexplored parameter regime for both classical and quantum computation protocols.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Transport-Generated Signals Uncover Geometric Features of Evolving Branched Structures
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Fabian H. Kreten, Ludger Santen, Reza Shaebani
Branched structures that evolve over time critically determine the function of various natural and engineered systems, including growing vasculature, neural arborization, pulmonary networks such as lungs, river basins, power distribution networks, and synthetic flow media. Inferring the underlying geometric properties of such systems and monitoring their structural and morphological evolution is therefore essential. However, this remains a major challenge due to limited access and the transient nature of the internal states. Here, we present a general framework for recovering the geometric features of evolving branched structures by analyzing the signals generated by tracer particles during transport. As tracers traverse the structure, they emit detectable pulses upon reaching a fixed observation point. We show that the statistical properties of this signal intensity – which reflect underlying first-passage dynamics – encode key structural features such as network extent, localized trapping frequency, and bias of motion (e.g., due to branch tapering). Crucially, this method enables inference from externally observable quantities, requiring no knowledge of individual particle trajectories or internal measurements. Our approach provides a scalable, non-invasive strategy for probing dynamic complex geometries across a wide range of systems.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
13 pages, 6 figures
Quantum quenches with long range interactions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Marianna Sorba, Nicolò Defenu, Gesualdo Delfino
We extend the theory of quantum quenches to the case of $ d$ -dimensional homogeneous systems with long range interactions. This is achieved treating the long range interactions as switched on by the quench and performing the derivation within the basis of asymptotic states of the short range interacting pre-quench theory. In this way we analytically determine the post-quench state and the one-point functions of local observables such as the order parameter. One implication is that, as in the short range case, some oscillations induced by the quench remain undamped at large times under conditions specified by the theory. This explains, in particular, why such undamped oscillations have been numerically observed also in presence of long range interactions.
Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
Can the Oxygen $2p$ Band Be Hole Doped?
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
The development of $ p$ -type oxide semiconductors remains impeded by the inherently low-lying valence-band maximum (VBM) dominated by O-2$ p$ states. A prevailing approach to mitigate this limitation is to elevate the VBM by introducing cation states that hybridize with O-2$ p$ orbitals or lie energetically above the O-2$ p$ level. Nevertheless, the $ p$ -type oxides reported to date exhibit limited hole mobilities. To expand the search space, it is essential to accurately understand the intrinsic difficulty of introducing holes into O-2$ p$ orbitals. Accordingly, we evaluated 845 oxides to identify those in which holes can be doped into O-2$ p$ bands. Our high-throughput screening revealed CaCdO$ _2$ as the only promising exemplar, in which the VBM is slightly hybridized with deep-lying Cd-3$ d$ states. Our screening suggests that hole doping into O-2$ p$ orbitals is extremely difficult and thus reinforces the effectiveness of the traditional ``VBM-raising strategy.’’
Materials Science (cond-mat.mtrl-sci)
This manuscript has been submitted to the Journal of the American Chemical Society for consideration
How oxygen influences the catalytic activity of iron during carbon nanotube nucleation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Ben McLean, Alister J. Page, Feng Ding
The catalytic activity of metal nanoparticles toward nucleation of single-walled carbon nanotubes (SWCNTs) is fundamental to achieving structure-controlled growth using catalytic chemical vapor deposition (CVD). Despite the success of oxidized catalysts in SWCNT growth, there is a lack of understanding regarding how oxygen influences the catalysts and the nucleation process. Quantum chemical molecular dynamics (MD) simulations employing density functional tight binding (DFTB) demonstrate that the kinetics of carbon nucleation on an iron nanoparticle catalyst can be tuned via oxygen loading. Increasing the oxygen content in the catalyst leads to activation of surface-bound carbon species and enhanced carbon chain growth due to respective weakening and strengthening of the C-C and Fe-C bonding. This is due to oxygen modulating the electronic structure of the iron catalyst, with the Fermi level of the catalyst increasing proportionally with oxygen content until the iron:oxygen stoichiometry reaches parity. The increase in Fe 3d states near the Fermi level also promotes the donation of electron density into unoccupied C 2p states, activating C-C bonds which in turn facilitates carbon chain growth and slows carbon ring condensation.
Materials Science (cond-mat.mtrl-sci)
19 pages, 3 Figures
Universal Relation between Spectral and Wavefunction Properties at Criticality
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Simon Jiricek, Miroslav Hopjan, Vladimir Kravtsov, Boris Altshuler, Lev Vidmar
Quantum-chaotic systems exhibit several universal properties, ranging from level repulsion in the energy spectrum to wavefunction delocalization. On the other hand, if wavefunctions are localized, the levels exhibit no level repulsion and their statistics is Poisson. At the boundary between quantum chaos and localization, however, one observes critical behavior, not complying with any of those characteristics. An outstanding open question is whether there exist yet another type of universality, which is genuine for the critical point. Previous work suggested that there may exist a relation between the global characteristics of energy spectrum, such as spectral compressibility $ \chi$ , and the degree of wavefunction delocalization, expressed via the fractal dimension $ D_1$ of the Shannon–von Neumann entropy in a preferred (e.g., real-space) basis. Here we study physical systems subject to local and non-local hopping, both with and without time-reversal symmetry, with the Anderson models in dimensions three to five being representatives of the first class, and the banded random matrices as representatives of the second class. Our thorough numerical analysis supports validity of the simple relation $ \chi + D_1 = 1$ in all systems under investigation. Hence we conjecture that it represents a universal property of a broad class of critical models. Moreover, we test and confirm the accuracy of our surmise for a closed-form expression of the spectral compressibility in the one-parameter critical manifold of random banded matrices. Based on these findings we derive a universal function $ D_{1}(r)$ , where $ r$ is the averaged level spacing ratio, which is valid for a broad class of critical systems.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Quantum Physics (quant-ph)
11 pages, 7 figures
Topological Signatures of Magnetic Phase Transitions with Majorana Fermions through Local Observables and Quantum Information
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-16 20:00 EDT
Karyn Le Hur, Fan Yang, Magali Korolev
The one-dimensional (1D) $ J_1-J_2$ quantum spin model can be viewed as a strong-coupling analogue of the Schrieffer-Su-Heeger model with two inequivalent alternating Ising couplings along the wire, associated to the physics of resonating valence bonds. Similar to the quantum Ising model, which differently presents a long-range Neel ordered phase, this model also maps onto a p-wave superconducting wire which shows a topological phase transition with the emergence of low-energy Majorana fermions. We show how signatures of the topological phase transition for the p-wave superconducting wire, i.e. a half Skyrmion, are revealed through local (short-range) spin observables and their derivatives related to the capacitance of the pairing fermion model. Then, we present an edge correspondence through the edge spin susceptibility in the $ J_1-J_2$ model revealing that the topological phase transition is a metal of Majorana fermions. We justify that the spin magnetization at an edge at very small transverse magnetic field is a good marker of the topological invariant. We identify a correspondence between the quantum information of resonating valence bonds and the charge fluctuations in a p-wave superconductor through our method ``the bipartite fluctuations’’. This $ J_1-J_2$ system may be realized in materials and engineered in quantum circuits, optical lattices.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
5 pages, References List and 3 figures, and Supplementary Material including 2 Figures
PAMBE growth of GaN nanowires on metallic ZrN buffers – a critical impact of ZrN layer thickness on the growth temperature
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Karol Olszewski, Zbigniew R. Zytkiewicz, Aleksandra Wierzbicka, Marek Guziewicz, Marta Sobanska
An impact of thin metallic ZrN layers on Si and sapphire wafers on substrate temperature during MBE growth of GaN nanowires is studied. Using nucleation kinetics of GaN as a sensitive probe we show that a thin ZrN layer strongly increases the substrate temperature, which significantly affects the dimensions and density of the nanowires. To quantify the effect we developed a technique of optical pyrometer calibration that allows reliable determination of emissivity, and thus precise measurement of temperature of substrates with unknown optical parameters, such as ZrN buffers of various thicknesses. Our results show that emissivity of ZrN-coated Si and sapphire wafers differs significantly from the bulk ZrN and increases drastically for films thinner than ~100 nm. Simple calculations indicate that ignoring the influence of the thin film may lead to huge errors in temperature readings and consequently to losing the growth control. Then, we show that we can compensate for the impact of ZrN buffer on substrate temperature and grow identical nanowire arrays on Si substrates with and without ZrN layers. Finally, having identical arrays of GaN nanowires we used X-ray diffraction to compare nanowire arrangements on Si and ZrN/Si substrates with a thin SiN nucleation layer.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Vane rheology of a fiber-reinforced granular material
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-16 20:00 EDT
Ladislas Wierzchalek, Georges Gauthier, Baptiste Darbois-Texier
The addition of a small quantity of flexible fibers in a granular material is an efficient technique to increase the yield stress of the material. While the influence of fiber addition on the mechanical strength of granular media has been studied, much less is known about the flow properties of grain-fiber mixtures. In this article, we explore the effect of flexible fibers on the flow behavior of grain-fiber mixtures above the yield stress. We use a vane geometry to study the rheology of a dry granular material mixed with flexible fibers with different volume fractions and properties. The vane is immersed in the material, and the granular pressure increases with the depth of immersion. When the vane begins rotating, we observe a transient regime, which depends on the number of blades and is associated with the mobilization of material between the blades. Following this transient phase, a stationary regime is reached. By measuring and modeling the stationary flow that develops around the vane, we deduce the effective friction coefficient of the material from the torque measured on the vane. Following this approach, we investigate the effect of the fiber volume fraction and the aspect ratio on the effective friction coefficient of the grain-fiber mixture. Our results show that the effective friction coefficient increases linearly with fiber volume fraction and exponentially with fiber aspect ratio. These findings provide new fundamental insights into the flow properties of grain-fiber mixtures.
Soft Condensed Matter (cond-mat.soft)
(Vol.69, Issue 3), 2025
Magnon-plasmon hybridization mediated by Dzyaloshinskii-Moriya interaction in two-dimensional crystals: tuning with electric field
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Wojciech Rudziński, Mirali Jafari, Józef Barnaś, Anna Dyrdał
Recently, a mechanism of magnon-plasmon hybridization in ferromagnetic and antiferromagnetic systems, based on spin-orbit interaction associated with mobile (conduction) electrons has been proposed. Here, we consider another mechanism of magnon-plasmon hybridization, which is based on spin-orbit coupling attributed to localized spins and leading to the antisymmetric exchange (Dzyaloshinskii-Moriya) interaction. The basic element of the mechanism of magnon-plasmon coupling relies on the modification of the Dzialoshinskii-Moriya interaction by the electric field associated with plasmons. We show, that the modification of the Dzialoshinskii-Moriya components due to electric field accompanied by plasmons may lead to hybridization of magnons and plasmons. Moreover, we also show that an external electric field normal to the layer (due to a gate voltage, for instance) can be used as a tool to tune the strength of the magnon-plasmon coupling.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Inverse Thermodynamics: Designing Interactions for Targeted Phase Behavior
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-16 20:00 EDT
Camilla Beneduce, Giuseppe Mastriani, Petr Šulc, Francesco Sciortino, John Russo
The traditional goal of inverse self-assembly is to design interactions that drive particles toward a desired target structure. However, achieving successful self-assembly also requires tuning the thermodynamic conditions under which the structure is stable. In this work, we extend the inverse design paradigm to explicitly address this challenge by developing a framework for inverse thermodynamics, i.e. the design of interaction potentials that realize specific thermodynamic behavior. As a step in this direction, using patchy particle mixtures as a model system, we demonstrate how precise control over both bonding topology and bond energetics enables the programming of targeted phase behavior. In particular, we establish design principles for azeotropic demixing and show how to create mixtures that exhibit azeotropy at any prescribed composition. Our predictions are validated through Gibbs-ensemble simulations [A.Z. Panagiotopoulos,Molecular Physics 61, 813-826 (1987)]. These results highlight the necessity of coupling structural design with thermodynamic engineering, and provide a blueprint for controlling complex phase behavior in multi-component systems.
Soft Condensed Matter (cond-mat.soft)
9 figures
Current-Controlled Magnon-Magnon Coupling in an On-Chip Cavity Resonator
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Hanchen Wang, William Legrand, Richard Schlitz, Pietro Gambardella
Harnessing spin currents to control magnon dynamics enables new functionalities in magnonic devices. Here, we demonstrate current-controlled magnon-magnon coupling between cavity and boundary modes in an ultrathin film of Bi-doped yttrium iron garnet (BiYIG). Cavity modes emerge in a BiYIG region between two Pt nanostripes, where interfacial anisotropy modifies the magnon dispersion. These modes hybridize with boundary magnons confined within the Pt-capped BiYIG, resulting in an anticrossing gap. Modeling based on dipole-exchange spin-wave dispersion accurately reproduces the observed modes and their hybridization. Spin current injection via the spin Hall effect in a Pt nanostripe disrupts the cavity boundary conditions and suppresses both cavity modes and hybridization upon driving the system beyond the damping compensation threshold. Furthermore, tuning the microwave power applied to a microstrip antenna enables controlled detuning of the anticrossing gap. Our findings provide a platform for exploring spin current-magnon interactions and designing on-chip reconfigurable magnonic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Nano Letters 25, 22, (2025) 9090-9097
Beyond Characteristic Equations: A Unified Non-Bloch Band Theory via Wavefunction Data
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Non-Hermitian systems play a central role in nonequilibrium physics, where determining the energy spectrum under open boundary conditions is a fundamental problem. Non-Bloch band theory, based on the characteristic equation $ \text{det}[E - H(\beta)] = 0$ , has emerged as a key tool for this task. However, we show that this framework becomes insufficient in systems with certain symmetries, where identical characteristic equations can yield different spectra. To resolve this, we develop a unified theory that incorporates additional wavefunction information beyond the characteristic equation. Our framework accurately captures spectral properties such as the energy spectrum and the end-to-end signal response in a broad class of systems, particularly those with high symmetry. It reveals the essential role of wavefunction information and symmetry in shaping non-Hermitian band theory.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
16 pages, 3 figures, including supplemental material
Bridging a gap: A heavy elastica between point supports
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-16 20:00 EDT
Grace K. Curtis, Ian M. Griffiths, Dominic Vella
We study the deformation and slip-through of a heavy elastic beam suspended above two point supports and subject to an increasing body force – an idealized model of a fibre trapped in the pores of a filter as flow strength increases, for example. Using both asymptotic and numerical techniques, we investigate the behaviour of the beam under increasing body force and the maximum force that can be supported before it must slip between the supports. We quantify this maximum body force as a function of the separation between the two supports. Surprisingly, we show the existence of a critical separation below which the beam can withstand an arbitrarily large body force, even in the absence of friction. This is understood as the limit of a catenary between the supports that is connected to (and supported by the tension in) a vertically hanging portion outside the supports. We explore how frictional forces impact the deformation and load-bearing capacity of the beam and show that our results are consistent with laboratory experiments.
Soft Condensed Matter (cond-mat.soft)
Orbital Pumping in Ferrimagnetic Insulators
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Hanchen Wang, Min-Gu Kang, Davit Petrosyan, Shilei Ding, Richard Schlitz, Lauren J. Riddiford, William Legrand, Pietro Gambardella
We report the detection of pure orbital currents generated by both coherent and thermal magnons in the magnetic insulator Bi-doped yttrium iron garnet (BiYIG). The pumping of orbital and spin currents is jointly investigated in nano-devices made of naturally oxidized Cu, pure Cu, Pt, and Cr. The absence of charge conduction in BiYIG and the negligible spin-to-charge conversion of oxidized Cu allows us to disambiguate the orbital current contribution. Comparative measurements on YIG and BiYIG show that the origin of the orbital pumping in BiYIG/oxidized Cu is the dynamics of the orbital magnetization in the magnetic insulator. In Cr, the pumping signal is dominated by the negative spin Hall effect rather than the positive orbital Hall effect, indicating that orbital currents represent a minority of the total angular momentum current pumped from the magnetic insulator. Our results also evidence that improving the interfacial transparency significantly enhances pumping efficiencies not only for spin, but also for orbital currents.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Physical Review Letters 134, 126701 (2025)
Thermal conductivity minimum with thickness in ultrathin films
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
The thermal properties of solids under nanoscale confinement are currently not understood at the atomic level. Recent numerical studies have highlighted the presence of a minimum in the thermal conductivity as a function of thickness for ultrathin films at a thickness about 1-2 nm, which cannot be described by existing theories. We develop a theoretical description of thin films which predicts a new physical law for heat transfer at the nanoscale. In particular, due to the strong redistribution of phonon momentum states in reciprocal space (with a transition from a spherical Debye surface to a different homotopy group $ \mathbb{Z}$ at strong confinement), the low-energy phonon density of states no longer follows Debye’s law but rather a cubic law with frequency, which then crosses over to Debye’s law at a crossover frequency proportional to the average speed of sound of the material and inversely proportional to the film thickness. Concomitantly, this implies that the phonon population becomes dominated by low-energy phonons as confinement increases, which then leads to a higher thermal conductivity under extreme confinement. The theory is able to reproduce the thermal conductivity minimum in recent molecular simulations data for ultrathin silicon and provides useful guidelines as to tune the minimum position based on the mechanical properties of the material.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other), Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
Towards 4D modelisation of thermal-field emission from semiconductors
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Salvador Barranco Cárceles, Aquila Mavalankar, Veronika Zadin, Ian Underwood, Andreas Kyritsakis
The theoretical picture of thermal field-emission (TFE) from semiconductors has been limited to 1D and 2D models. This can be attributed to the complex and interdependent phenomena that is involved in TFE from semiconductors which makes the calculations cumbersome. Such limitations result in a partial understanding of the underlying physics of semiconducting surfaces under high electrical fields, which requires the addition of the temporal dimension (4D) to yield a realistic model. Here we develop a 3D model of TFE from semiconductors that can take arbitrary geometries and doping levels. Our model successfully reproduces the characteristic saturation plateau of some semiconductors, as well as its dependence in temperature. The model is found to be in good agreement with experimental data from ntype Germanium at a qualitative level. We propose this model as a platform for future extensions into the full 4D framework, incorporating temporal dynamics for a more complete and predictive description of thermal-field emission from semiconductors.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Hydrodynamics of chiral nematics in a channel and sudden contraction geometry
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-16 20:00 EDT
This study investigates the influence of chirality, viscous effects, and confinement geometry on the flow dynamics and defect structures of cholesteric liquid crystals (CLCs) using numerical simulations. As chiral strength increases, $ \pi$ -twist defects form at low chirality and progressively organize into hexagonal domains resembling blue phase–like (BP-like) structures at higher chirality. At sufficiently high chirality and aspect ratios, skyrmion-like configurations emerge, indicating the formation of dynamic analogs of equilibrium phases under flow. Sudden contraction geometries reveal how aspect ratio and elastic interactions promote flow disturbances and defect development. Analyses of velocity and scalar order parameter ($ S$ ) distributions demonstrate strong coupling between molecular alignment and hydrodynamic fields, with localized vortices forming around $ \tau^-$ defects in regions of low $ S$ and velocity. Temporal evaluations of velocity fluctuations uncover chaotic flow regimes at low Ericksen numbers, characterized by irregular defect motion and skewed probability density functions. These findings offer new insights into CLC structure formation and flow behavior, with potential applications in defect engineering, microfluidics, soft robotics, and photonic materials.
Soft Condensed Matter (cond-mat.soft), Mathematical Physics (math-ph)
Quick starch guide: A perspective on shear thickening in dense non-Brownian suspensions
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-16 20:00 EDT
Cécile Clavaud, Abhinendra Singh
In this article, we provide a brief perspective on recent developments in the study of shear thickening in dense suspensions. We give a rapid overview of the state of the art and discuss current models aiming to describe this particular rheology. Although most of the experiments and simulation studies are conducted in “ideal” flows, where the sample is confined without an open boundary condition, we have decided to highlight more realistic flow conditions. We further provide an overview on how to relate the recently proposed constitutive models to these more practical flow conditions like pipe flow or flow down an incline.
Soft Condensed Matter (cond-mat.soft), Disordered Systems and Neural Networks (cond-mat.dis-nn), Materials Science (cond-mat.mtrl-sci), Fluid Dynamics (physics.flu-dyn), Geophysics (physics.geo-ph)
Perspective on recent advances in shear thickening suspensions. Comments/suggestions to improve this arXiv submission are most welcome. Please contact us, and we will try to incorporate them. arXiv admin note: text overlap with arXiv:cond-mat/9803197 by other authors
Quantum Critical Eliashberg Theory
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-16 20:00 EDT
Ilya Esterlis, Joerg Schmalian
Quantum criticality plays a central role in understanding non-Fermi liquid behavior and unconventional superconductivity in strongly correlated systems. In this review, we explore the quantum critical Eliashberg theory, which extends conventional Eliashberg approaches to non-Fermi liquid regimes governed by critical fluctuations. We discuss the theoretical foundations and recent developments in the field, focusing on the interplay between electronic interactions and bosonic modes near quantum phase transitions as described in the Yukawa-coupled version of the Sachdev-Ye-Kitaev model. Special emphasis is placed on the breakdown of quasiparticle coherence, anomalous scaling behaviour, Cooper pairing without quasiparticles, and emergent universality in different physical settings. Starting from a zero-dimensional “quantum-dot” model, we discuss the generalization to higher spatial dimensions and demonstrate the connection between quantum-critical Eliashberg theory and holographic superconductivity. Our analysis provides a perspective on how quantum criticality shapes the dynamics of strongly correlated metals and superconductors.
Strongly Correlated Electrons (cond-mat.str-el)
31 pages, 7 figures. Review article, to appear in Annual Review of Condensed Matter Physics
Synaptic plasticity in Co/Nb:STO memristive devices: The role of oxygen vacancies
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-16 20:00 EDT
Walter Quiñonez, Anouk Goossens, Diego Rubi, Tamalika Banerjee, María José Sánchez
Neuromorphic computing aims to develop energy-efficient devices that mimic biological synapses. One promising approach involves memristive devices that can dynamically adjust their electrical resistance in response to stimuli, similar to synaptic weight changes in the brain. However, a key challenge is understanding and controlling the coexistence of different types of synaptic plasticity, such as short-term and long-term plasticity. In this work, we show that plasticity behaviors in Co/Nb:STO Schottky memristors originate from oxygen vacancy electromigration, which modulates the Schottky barrier and enables both short-term and long-term plasticity. Our experiments reveal that resistance changes follow a power-law during reading (short-term plasticity) and increase stepwise with successive pulses (long-term memory retention). These behaviors are successfully reproduced by our model, which demonstrates the correlation between oxygen vacancy distribution and Schottky barrier modulation. Our findings highlight these memristors as promising candidates for neuromorphic applications.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 5 figures
APL Electron. Devices 1, 026120 (2025)
Most probable paths for active Ornstein-Uhlenbeck particles
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Fluctuations play an important role in the dynamics of stochastic systems. In particular, for small systems, the most probable thermodynamic quantities differ from their averages because of the fluctuations. Using the Onsager Machlup variational formalism we analyze the most probable paths for non-equilibrium systems, in particular active Ornstein-Uhlenbeck particles (AOUP), and investigate how the entropy production along these paths differ from the average entropy production. We investigate how much information about their non-equilibrium nature can be obtained from their extremum paths and how these paths depend on the persistence time and their swim velocities. We also look at how the entropy production along the most probable paths varies with the active noise and how it differs from the average entropy production. This study would be useful to design artificial active systems with certain target trajectories.
Statistical Mechanics (cond-mat.stat-mech)
5 figures
Phys. Rev. E 107 (2023), 054130
Exploring light-induced phases of 2D materials in a modulated 1D quasicrystal
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-16 20:00 EDT
Yifei Bai, Anna R. Dardia, Toshihiko Shimasaki, David M. Weld
Illuminating integer quantum Hall matter with polarized light can drive quantum phase transitions. Technical limitations on laser intensity and material purity make such experiments challenging in the solid state. However, the Harper-Hofstadter mapping which relates a two-dimensional integer quantum Hall system to a 1D quasicrystal enables the same polarization-dependent light-induced phase transitions to be observed using a quantum gas in a driven quasiperiodic optical lattice. We report experimental results from such a 1D quantum simulator of 2D integer quantum Hall matter driven by light of variable polarization. We observe an interlaced phase diagram of localization-delocalization phase transitions as a function of drive polarization and amplitude. Elliptically polarized driving can stabilize an extended critical phase featuring multifractal wavefunctions; we observe signatures of this phenomenon in subdiffusive transport. In this regime, increasing the strength of the quasiperiodic potential can enhance rather than suppress transport. These experiments demonstrate a simple method for synthesizing exotic multifractal states and exploring light-induced quantum phases across different dimensionalities.
Quantum Gases (cond-mat.quant-gas), Disordered Systems and Neural Networks (cond-mat.dis-nn)
6 pages, 4 figures + 2 extended data, and supplementary information
Ising versus infinite randomness criticality in arrays of Rydberg atoms trapped with non-perfect tweezers
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-16 20:00 EDT
Jose Soto-Garcia, Natalia Chepiga
Chains of Rydberg atoms have emerged as an amazing platform for simulating quantum physics in low dimensions. This remarkable success is due to the versatility of lattice geometries achieved by trapping neutral atoms with optical tweezers. On a given lattice, the competition between the repulsive van der Waals potential and the detuning of the laser frequency brings the atoms to highly excited Rydberg states, leading to a variety of exotic phases and quantum phase transitions. Experiments on the simplest one-dimensional array of Rydberg atoms have stimulated tremendous progress in understanding quantum phase transitions into crystalline phases. In addition to standard conformal transitions, numerical simulations have predicted two exotic chiral transitions and a floating phase, raising the question of their experimental realization. However, in reality, optical tweezers have a finite width, which results in small deviations in interatomic distances and disorder in interaction strength. However, disorder can affect the nature of transitions. Infinite randomness criticality in the random transverse-field Ising chain is perhaps the most prominent examples. In this paper, we demonstrate how the disorder typical for Rydberg experiments alters the Ising transition to the period-2 phase. Following the experimental protocol closely, we probe the nature of quantum criticality with Kibble-Zurek dynamics. While we clearly observe infinite randomness for strong disorder and large system sizes, we also report a crossover into a clean Ising transition, which is visible for small system sizes and weak disorder. Our results clearly demonstrate an additional technical constraint on the scalability of Rydberg-based quantum simulators.
Strongly Correlated Electrons (cond-mat.str-el)
Robustness of Floquet topological phase at room temperature: a first-principles dynamics study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-16 20:00 EDT
Nonadiabatic Thouless pumping of electrons is studied within the framework of topological Floquet engineering, particularly focused on how atomic lattice dynamics affect the emergent Floquet topological phase in trans-polyacetylene under the driving electric field. As similarly done in the earlier work [Zhou and Kanai, J. Phys. Chem. Lett., 12, 4496 (2021)], the real-time time-dependent density functional theory and Ehrenfest dynamics simulations were used to investigate the extent to which the number of pumped charges remains equal to the topological invariant, the winding number, when the temperature effect of ions and the dynamical coupling of electrons and ions are taken into account. Our theoretical work shows that the Floquet topological phase remains intact but the condition on the driving field necessary for observing the topological phase becomes more limiting.
Materials Science (cond-mat.mtrl-sci)
Entropy production in active Rouse polymers
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-16 20:00 EDT
Active polymers are the archetype of nonequilibrium viscoelastic systems that constantly consume energy to produce motion. The activity of many biopolymers is essential to many life processes. The entropy production rate quantifies their nonequilibrium nature through the breaking of the time reversal symmetry. In this work we build an analytical model of active polymers as active Rouse polymers where the beads are active Ornstein Uhlenbeck particles and calculate their entropy production. The interactions between the beads are decoupled through the normal mode analysis and the entropy production can be solved analytically. We obtain the contribution of each Rouse mode in the entropy production and the dependence of the entropy production on the polymer properties like length. We find that the entropy production is zero for a passive Rouse polymer in the presence of thermal bath as well as for an active Rouse polymer in the absence of thermal bath. For an active chain in the presence of a thermal bath the entropy production is nonzero. In this case we find that the local temporal entropy production dominates the nonlocal entropy production.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
2 figures
Physica Scripta, Volume 98 (2023), Number 4