Papers

The role of adaptive coupling in controlling collective noise-induced dynamics is demonstrated on an example of stochastic resonance in an ensemble of coupled overdamped bistable oscillators. Specifically, it is found that tuning the adaptive coupling parameters allows one to either enhance or suppress stochastic resonance and to shift the optimal noise intensity that yields the most regular stochastic oscillations. All the revealed effects are studied in numerical simulations for two kinds of adaptive coupling models. The first one is a simplified, phenomenological model designed such that the coupling becomes stronger for oscillators with larger differences between their dynamical variables (two configurations for local interaction and one option for global coupling are under consideration). The second one is a local memristive coupling model that provides a physically motivated realization of adaptive interactions with similar properties. In all the considered cases, adaptive coupling is shown to be a flexible stochastic resonance control tool, both in the absence and in the presence of the static coupling component.

Multi-photon interference is the resource most native to photonic quantum machine learning, yet experiments on photonic reservoirs have reported advantages, null results, and train-only effects. These outcomes cannot be compared: each measures task-dependent accuracy on different tasks and platforms. Here we resolve the question task-independently through the kernel geometry of boson-sampling feature maps. Interference redistributes feature variance across roughly twice as many effective dimensions as distinguishable-particle statistics, generating a large geometric separation between the corresponding kernels. The separation grows superlinearly with indistinguishability, is linear in Hong–Ou–Mandel visibility at small visibility for two to four photons, and retains approximately 80% of its magnitude at the source quality of current quantum processors. Under experimental sampling budgets the separation is learnable on adversarially constructed tasks (accuracy advantage +0.22 plus or minus 0.05) and an order of magnitude smaller on natural tasks, gated by kernel–task alignment. The results reconcile the existing experimental record and supply a pre-experimental protocol: kernel geometry establishes that an interference-specific learning resource exists, and task alignment determines whether a given task can access it; both are computable before committing significant hardware resources.

Pre-geometric Gravity investigates the non-metric features of spacetime near the Planck scale, from which the gravitational interaction arises as a low-energy effective theory via a mechanism of spontaneous symmetry breaking. With a view of amending the classical singularities found in black hole geometries, in this work we study pre-geometric black hole configurations with spherical symmetry, and present exact solutions for different pre-geometric theories in vacuum via the correspondence principle. These solutions are the pre-geometric analogue of the (anti-)de Sitter-Schwarzschild metric, from which such type of black hole geometry is thus expected to emerge. In one case, the pre-geometric solution also exhibits an (anti-)de Sitter core of Planckian size. The main result is supplemented with an analysis of the pre-geometric version of Birkhoff's theorem.

Nitrogen-vacancy (NV) centre ensembles are leading room-temperature magnetometers, but their sensitivity is usually extracted from a single resonance and relies on external microwave and bias-field hardware. This work proposes a chip-scale NV magnetometer built around a one-dimensional YIG/CoFeB magnonic crystal, in which a single structural defect forms a passive magnonic cavity and integrated permanent magnets supply the bias field. Micromagnetic simulations show a defect-localised spin-wave mode at 2.910 GHz inside the 2.5-3.0 GHz magnonic band gap, 40 MHz from the NV zero-field splitting, with a band structure that matches an independent plane-wave calculation. A Tavis-Cummings/Lindblad model in which the microwave reaches the NV ensemble through this mode predicts a hyperfine-resolved optically detected magnetic resonance spectrum that is strong only within the mode linewidth, and a dispersive homodyne response with one steep edge per $^{14}$N hyperfine line. The master-equation solutions agree with the closed-form homodyne steady state ($R^2 > 0.9999$) and with an approximate analytic ODMR theory (peak positions within 0.012 MHz). For a critically coupled readout with room-temperature electronics, combining the three edges gives a projected sensitivity of 93 pT/$\sqrt{\rm Hz}$, a $\sqrt{3}$-fold gain over the best single edge. Mapping the sensitivity against the NV-magnon coupling reveals an optimum near $g_{\rm ens}/2\pi \approx 0.2$-$0.4$ MHz, where it reaches 72 pT/$\sqrt{\rm Hz}$ for a 0.64 MHz spin linewidth and 19 pT/$\sqrt{\rm Hz}$ for 0.17 MHz, with thermal limits of 6.6 and 1.7 pT/$\sqrt{\rm Hz}$. The antenna-mode coupling, the NV-magnon coupling and the spin linewidth are therefore the main design levers.

Higher-frequency power in Hall-thruster plume-probe signals can arise from both harmonics of a repeatable breathing waveform and fluctuations about it, complicating spectral interpretation. We decompose 197 paired records from 20 sequentially sampled probe-pair geometries at one operating condition, estimating each phaseconditioned waveform from other records at the same geometry. The residual accounts for 87.1% and 99.7% of measured power in the 0.2-0.5 and 0.5-1 MHz bands, respectively, as medians across geometries. The repeatable waveform, however, reproduces the principal breathing-harmonic bicoherence structure. Residual power remains modulated by breathing phase after waveform removal, exceeding geometry-specific 95thpercentile circular-shift thresholds in both bands at all 20 geometries. Residual bicoherence is substantially weaker than that of the measured signal but exceeds record-specific random-phase thresholds in 195 of 197 records. An exact component expansion further shows that the all-waveform term dominates a specified signed third-order statistic over the fixed 50-80 kHz band near the second breathing harmonic. These results distinguish band-power allocation from harmonic organization within the evaluated frequency ranges. The attribution concerns uncalibrated probe-chain signals and does not identify distinct physical modes or measure energy-transfer rates. The findings motivate assessing repeatable-waveform contributions before interpreting breathing-harmonic bicoherence as evidence of interactions among residual fluctuations.

We study photon conversion into light particles, such as dilatons, axions, and gravitons, induced by background magnetic fields, and formulate the resulting evolution in terms of the Stokes parameters. We show that photon conversion reduces to an effective non-unitary evolution of the photon sector. In the perturbative regime, the Hermitian and anti-Hermitian parts of the effective photon Hamiltonian are related through Kramers–Kronig relations, revealing that the changes in the Stokes parameters are not independent. We apply this general framework to photon evolution in Gaussian stochastic magnetic fields with possible helicity, and derive the ensemble-averaged evolution of the Stokes parameters. We find that two nonzero contributions arise even in the absence of magnetic helicity, which respectively correspond to the overall attenuation of all the Stokes parameters and to an irrelevant overall phase. We also find that magnetic helicity gives rise to two additional contributions, one of which changes the circular polarization while the other induces a rotation of linear polarization. These contributions form two Kramers–Kronig pairs. In particular, photon conversion induced by magnetic helicity is accompanied by both circular-polarization and birefringent responses. The same structure appears in dilaton-photon, axion-photon, and graviton-photon systems, revealing universality of photon conversion in magnetic fields.

Altermagnetic materials, characterized by vanishing net magnetization and momentum-dependent spin splitting, provide a unique platform for realizing unconventional superconducting states without the detrimental stray fields. Here, we demonstrate long-distance Josephson supercurrent transport through epitaxial thin films of the strained altermagnet CrSb. We observe a dissipationless supercurrent across a lateral spacer distance of 150 nm in a CrSb-based Josephson junction, exceeding the conventional spin-singlet coherence length by nearly two orders of magnitude. This supercurrent is further accompanied by a well-defined magnetic-field-induced quantum interference pattern, providing direct evidence for genuine Josephson coupling. Our results reveal altermagnets as a promising route toward generating long-distance supercurrents without macroscopic magnetic stray fields, opening new opportunities for superconducting spintronic applications.

The Belle and Belle II experiments provide a powerful platform for beyond-the-Standard-Model searches, particularly in tau and dark sectors. This summary reports include a measurement of CP violation in $\tau^- \to \pi^- K_S^0 \nu_{\tau}$, a search for $\tau^- \to \ell^- \eta$, a search for axion-like particles via $e^+ e^- \to \gamma a (\to \gamma\gamma)$ using Belle II data, and a search for feebly interacting particles in $B \to h X_{\rm inv}$ decays using Belle data.

Our automated analysis of photoelectron yield spectroscopy (PYS) estimates the threshold Ith and the exponent n of a single power law for every spectrum. When this model fits poorly, however, the analysis cannot tell whether the data or the model is at fault. Here we present residual diagnostics that separate the two causes. The exponent is scanned continuously on a 1/n-power fit with an Akaike information criterion (AIC) based on the mean absolute error (MAE), and the spread of the resulting Akaike weights ($P \times \Delta n$) quantifies the uncertainty of the estimate. The normalized MAE (NMAE) and the RMSE-to-MAE ratio (RMR) assess the data quality, the Durbin-Watson (DW) statistic assesses the model adequacy, and the three checks are reported in parallel. With criteria set from an Au reference, the diagnostics were applied to 60 continuous measurements in air of four HF-treated Si samples. For heavily doped p-type Si, DW fell below its criterion, whereas the means of NMAE and RMR remained within their criteria. Prompted by this flag, we fitted the spectrum with a two-component model with fixed exponents (n = 1 and 2.5); the AIC decreased by 56, DW increased from 0.86 to 1.99, and the two components set in at 4.70 and 5.28 eV. For heavily doped n-type Si, the change during air exposure was consistent with a single component. The diagnostics thus identify the spectra that require a multi-component analysis without assuming an emission mechanism.

Isotope effects govern fractionation and modulate reactivity, with applications from hydrogen energy to environmental science and catalysis, yet predicting them requires resolving small isotope-dependent free-energy differences that remain very challenging for conventional path-integral simulations in complex systems. Here we introduce iso-EPIGS, a path-integral coarse-graining framework built on a mass-differentiable neural network that reconstructs the mass- and temperature-dependent path integral centroid free-energy surface. Classical molecular dynamics on the learned surface yields rigorous isotope-resolved thermodynamics without explicit path-integral sampling. Benchmarks spanning gas, liquid, and crystalline phases, including liquid water and oxalic acid crystal, reproduce reference path-integral isotope free-energy differences, enthalpies, and lattice parameters at near classical computational cost. Crucially, iso-EPIGS trained solely on all-H and all-D isotopologues retains high accuracy for unseen partially deuterated isotopologues, demonstrating robust transferability across nuclear masses. Iso-EPIGS makes accurate isotope-effect simulations feasible for complex systems and lays the groundwork for foundation models of isotope effects across chemical space.

We investigate fermionic spectral functions in a two-current Gubser-Rocha background with linear-axion momentum relaxation. Serving as a comparison channel, the dipole coupling $p_1$ is found to produce a soft asymmetric reconstruction without opening a clean hard Mott gap. Our main analysis then focuses on two axion-dependent non-minimal couplings modulated by current mixing. The $p_2$ tensor channel suppresses the zero-energy Fermi peak and shifts the dominant spectral weight to finite frequencies, resulting in a flat-bottom reconstruction. In contrast, the $p_3$ vector channel creates a strong spectral asymmetry in momentum space, generating open, Fermi-arc-like segments. Varying the momentum-relaxation strength $\beta/\mu$ and the doping parameter $\chi$ reveals a channel-dependent response to the two-current background. Increasing $\beta/\mu$ generally broadens the $p_2$ response, whereas the one-sided $p_3$ feature varies non-monotonically under changes of the background parameters. These results clarify how current mixing, axion-induced momentum relaxation, and non-minimal fermion couplings jointly reshape holographic fermionic excitations. These results clarify how current mixing, axion-induced momentum relaxation, and non-minimal fermion couplings jointly reshape holographic fermionic excitations.

Integrated photonic quantum chips have emerged as a promising platform for realizing fault-tolerant photonic quantum computers. Compared with bulk-optics systems, integrated photonics offer compact device footprints, enhanced programmability, and exceptional stability, attributes that are essential for executing large-scale and computationally demanding quantum tasks. In this review, we provide a comprehensive overview of recent advances in both discrete-variable and continuous-variable universal photonic quantum computation. We survey progress in fault-tolerant architectures and state-of-the-art integrated platforms and highlight the key challenges that must be addressed to scale photonic systems toward full fault tolerance. Finally, we outline future opportunities and research directions aimed at bridging the gap between current proof-of-principle demonstrations and fully scalable quantum microprocessors.

While both neutrino propagation in photons and ultrarelativistic plasmas and neutrino oscillations in curved spacetimes have been studied extensively, their combination in a self-gravitating geometry appears not to have been considered previously. In this paper, we will investigate neutrino oscillations inside a static spherically symmetric spacetime, derived self-consistently from Einstein's equations, supported by ultrarelativistic matter. By relying on the geodesic motion and geometrical symmetries of the configuration, we will compute analytically the neutrino eikonal and spinoptics phase oscillations. Next, we will relate resonance phenomena to the physical interpretation of the background material inside which neutrinos travel for disentangling gravitational versus electroweak effects. We will inspect the effects of the pure gravitational and pure matter fields, and of the temperature in the neutrino oscillations; we will explain why our results are not coordinate artifacts, and we will certify our heuristic method by comparing with the asymptotic behaviours predicted by thermal field theory approaches. We will raise awareness on the relevance of the spinoptics phase shift entering the flavor conversion probability, should the neutrinos hit a curvature singularity. Theoretically, we will scrutinize the separate roles of geometrical symmetries versus physical features of the configuration, while astrophysically we will qualitatively discuss neutrino oscillations inside stars and in the Cosmic Microwave Background at different temperature and density conditions. Our research puts forward, in the context of the Tolman VI metric, an observational method for identifying naked singularities in our Universe: neutrinos would simultaneously be physically overlapped, in flavor-equilibrium and quantum-mechanically scrambled.

The survival probability $W_{\rm sur}$ of an excited compound nucleus against fission is a key factor determining the evaporation-residue cross section in the synthesis of superheavy nuclei. The $W_{\rm sur}$ for $^{292}$Fl formed in the $^{48}$Ca+$^{244}$Pu reaction was investigated, with particular attention to the coupling between neutron multiplicity and fission competition during the de-excitation cascade. The entrance-channel capture and fusion cross sections are obtained within the dinuclear system model, while the neutron–fission competition is treated using the Vandenbosch–Huizenga formalism with the Kramers and Strutinsky corrections and a fission barrier damped with temperature and angular momentum. The survival probability is calculated using two treatments of the evaporation–fission cascade. In the conventional factorized approach, the realization probability of a given $xn$ channel is treated independently of the neutron–fission competition, with the branching ratios evaluated along a mean excitation-energy trajectory. In the coupled approach, the full excitation-energy population is propagated through the cascade, so that neutron multiplicity and competition with fission are determined simultaneously at the energy actually reached by each nucleus. The comparison shows that the factorized treatment underestimates the $3n$ survival probability by factors of 17 and 24 at $E^*=39$ and 47 MeV, respectively, while its effect on the $4n$ channel is considerably smaller. The resulting $3n$ and $4n$ evaporation-residue excitation functions reproduce eight of the fourteen measured cross sections within a factor of two. A comparison of two prescriptions for the cold fission barrier further shows that differences of less than 1 MeV can change $W_{\rm sur}$ by more than an order of magnitude.

Encapsulation of two-dimensional (2D) materials with hexagonal boron nitride (hBN) is widely used to fabricate ultraclean van der Waals (vdW) heterostructures for optoelectronic and quantum transport studies. These devices are often operated under strong out-of-plane displacement fields that tune the electronic properties of the active 2D material, while the surrounding hBN is typically assumed to remain electronically inert. This assumption, however, neglects defect states that are present even in high-quality hBN crystals. Here, we probe their response to the applied displacement field using monolayer graphene encapsulated between hBN crystals as a sensitive charge sensor. Increasing the displacement field induces notable charge transfer between graphene and hBN, producing additional electron doping of 10-20x10^9 cm^(-2) even at the moderate displacement field (~0.5 V nm^(-1)), while simultaneously increasing carrier-density inhomogeneity of the graphene layer. Both effects are consistent with ionization of defect states within the hBN bandgap, with the bulk density ~1-7x10^(-5) nm^(-3) varying across different hBN crystals. Our results show that displacement-field-induced defect ionization in hBN can modify the electronic response of vdW heterostructures, with direct implications for device design and interpretation of experiments.

Two dimensional Janus semiconductors integrating spin-valley coupling, piezoelectricity, and tunable optical responses offer a platform for multifunctional nanodevices. Here, first-principles calculations reveal complementary composition and strain effects in CrSiCN4 and CrGeCN4 monolayers. Both are found to be nonmagnetic direct-gap semiconductors, with gaps of 1.23 and 1.09 eV using the Perdew-Burke-Ernzerhof functional including spin-orbit coupling, respectively. HSE06 hybrid-functional calculations retain the direct-gap character, yielding gaps of 1.46 eV for CrSiCN4 and 1.19 eV for CrGeCN4. Opposite out-of-plane spin character and Berry curvature emerge at K and K'. Biaxial strain reduces the respective gaps from 1.59 to 0.86 eV and 1.44 to 0.63 eV, drives direct-to-indirect transitions, and redshifts absorption while preserving valley spin contrast. CrGeCN4 exhibits larger in-plane piezoelectric response, whereas CrSiCN4 exhibits larger out-of-plane magnitude. Band-edge alignment satisfies the oxygen evolution reaction requirement but provides insufficient driving force for the hydrogen evolution reaction, motivating further strain-induced band-edge modulation toward overall water splitting. These results establish composition and strain as complementary controls for tailoring Cr-based Janus monolayers for valleytronic, optoelectronic, electromechanical, and photocatalytic applications.

A Poisson's ratio near -1 indicates only that the bulk modulus is small compared with the shear modulus. In solid-void structures, the mechanism that frees the dilation usually weakens the resistance to shear as well, resulting in both moduli becoming small. In two-dimensional linear elasticity, we demonstrate that this loss is not inevitable. We consider a honeycomb of regular hexagonal blocks of a single incompressible isotropic elastic solid, joined along their whole edges by ideal interfaces that allow relative sliding along a direction inclined to the edge normal. Collective infinitesimal block rotations produce an exact dilational mechanism, so the effective bulk modulus vanishes, while sixfold symmetry ensures isotropy. The interfaces, however, transmit traction along their whole length. In a solid-void realization, each interface is replaced with fine solid plates separated by void, which bend easily yet retain their capacity to transmit axial force. Such dilational materials, which expand or contract freely while resisting every change of shape, could serve as interlayers that accommodate thermal or swelling mismatch while still transmitting shear, and as components in stents and deployable structures that change size without changing shape. An explicit, statically admissible stress field and the complementary energy principle yield a rigorous lower bound on the retained shear modulus, and a limiting argument transfers this bound to the solid-void mixtures. The honeycomb retains more than four-fifths of its constituent's shear modulus at zero bulk modulus: the supremum S of the normalized shear modulus of such mixtures satisfies S > 0.8528 > 4/5, exceeding the value attained by Milton's construction.

Conventional diffractive deep neural networks (D2NNs) treat polarization as independent channels and rely on scalar or semi-vectorial propagation models, which neglect cross polarization coupling and vector diffraction. Here we propose a vector D2NN (V-D2NN) that embeds the full vector angular spectrum method into the end-to-end training pipeline. This physically rigorous framework describes vectorial light-matter interactions across cascaded diffractive layers, enabling direct optimization of polarization conversion, spin-orbit coupling, and vectorial interference without external polarization optics. We demonstrate the V-D2NN on polarization-multiplexed tasks–ector beam generation, polarization dependent imaging and classification, and multiple channel optical encryption–where it consistently outperforms scalar and semi-vectorial counterparts. In longitudinal-field engineering, the V-D2NN actively shapes a prescribed longitudinal field with a normalized correlation of 0.839, a capability inaccessible to scalar-propagation models. An open-source training framework is also provided to support further development of vectorial diffractive optics for computing, sensing, and communications.

In this work, we investigate the late-time expansion history and geometric diagnostics of logarithmic and exponential Finsler–Randers–Sasaki (FRS) cosmological models. We constrain both scenarios using cosmic chronometers, Baryon acoustic oscillations, and Pantheon+ Type~Ia supernovae, considering baseline fits as well as configurations calibrated with the local SH0ES distance-ladder prior. In the uncalibrated case, both profiles provide consistent descriptions of the late-time expansion history. Incorporating the SH0ES prior increases the inferred Hubble constant and modifies the inferred acoustic scale, reflecting the interplay between the local distance-ladder calibration and the BAO distance scale. Cosmographic reconstructions reveal a smooth transition from deceleration to acceleration at intermediate redshifts. Over the observationally relevant redshift range, both models exhibit a non-phantom, quintessence-like effective dark-energy sector. Finally, statefinder diagnostics distinguish the two FRS geometries: the logarithmic model remains relatively close to the canonical flat $\Lambda\mathrm{CDM}$ fixed point, whereas the exponential model follows a distinct dynamical trajectory. These results demonstrate that, despite their similar background expansion histories, the two FRS constructions can exhibit substantially different higher-order kinematic signatures.

Precise shaping of surface acoustic waves (SAWs) on anisotropic piezoelectric substrates is complicated by elastic anisotropy and electromechanical coupling. Here we introduce a continuous diffractive acoustic lens (CDAL), in which weak phase-velocity perturbations produced by subwavelength metallization, together with diffraction, drive lateral field redistribution. An anisotropic thin-element propagation model enables efficient inverse design of the CDAL contour. Laser Doppler vibrometry verifies prescribed lateral field profiles and multichannel beam splitting with unequal widths. By combining continuous diffractive modulation with discrete source-phase encoding, we further shape the lateral field into a Bessel profile, demonstrating joint amplitude-and-phase control. This work provides a high-precision and fabrication-compatible mechanism for on-chip SAW field modulation.

We compute the thermal photon production rate from a hot and dense quark-gluon plasma. While the mutual cancellation of the intermediate momentum cutoff $k_c$ between the hard and soft regimes in the presence of finite baryon density has been previously established only numerically, we demonstrate here, for the first time, that this cutoff independence can be shown analytically even in the presence of a nonzero quark chemical potential $\mu$. This resolves a long-standing issue addressed in Ref.[1]. The final expression for the photon rate can be treated as a generalization of the results obtained in Refs.[2,3] in the presence of $\mu$ and can be implemented directly in the space-time evolution of a hot and dense QGP medium using relativistic hydrodynamics.

Constraint-preserving exchange drivers allow many coupling graphs that preserve the same feasible sector, but exhibit different minimum gaps along an annealing path. We derive an exchange-resolved sensitivity of the normalised minimum gap for fixed-cardinality Laplacian drivers sharing a Dicke ground state, and apply it to identify locally favourable modifications of the driver. Numerical experiments indicate this sensitivity reliably predicts beneficial infinitesimal changes, but its reliability decreases when the same direction is extended to a finite edge replacement. The gap landscape tracking reveals one mechanism of this loss of reliability. Improving the active bottleneck can expose a competing minimum, with a more extensive reorganisation of the low-energy subspace. We call this the "repair-and-expose" mechanism and observe it in both dense quadratic and sparse frustrated objective families. This motivates relinearizing the response when competing minima become co-active. In the tested oracle setting, a tied-minimum max-min update is substantially more reliable than continuing the original direction or optimizing only the incoming minimum. Supporting finite-size search and selector tests show that this local information can remain useful beyond the infinitesimal limit, while its practical extraction depends on the driver geometry and identification of the relevant low-energy competitors. These results connect local exchange-resolved gap sensitivity to bottleneck migration and conditional driver redirection.

Variational quantum algorithms are often limited by barren plateaus: gradients vanish as circuit size and depth increase, making quantum neural networks difficult to train. We propose Q-Capsule, a localized capsule-based quantum neural architecture that mitigates this problem through register partitioning, local readout, sparse inter-capsule coupling, trainable data re-uploading, and Quantum Fisher Information Matrix (QFIM)-guided adaptive depth growth. By restricting the dominant support of each observable to a small capsule and controlling inter-capsule entanglement, Q-Capsule preserves useful gradient signals while retaining communication between local quantum representations. As the register width increases, Q-Capsule consistently maintains stable gradient variance, whereas globally entangling baselines exhibit exponential suppression with a log-gradient-variance slope near -ln 2 per qubit. Q-Capsule also produces more structured optimization landscapes, higher parameter efficiency, improved robustness to depolarizing noise, and lower measurement requirements. Its adaptive policy achieves 98.1% accuracy on binary classification and 97.7% on four-class classification, while using approximately 73% fewer two-qubit gates than the fixed-deep model on the multiclass task.

Superconducting diodes (SDs) are devices that rectify supercurrent through the difference in the superconducting critical current (Ic) between forward and reverse current directions. For bringing such SDs closer to practical superconducting power electronics applications, a combination of both high rectification efficiency ({\eta}) and a large Ic difference ({\Delta}Ic) is required. Here, we propose and demonstrate a coil-shaped superconducting wire device concept to induce a large SD effect, arising from the compensation between an external magnetic field (Hext) and the field generated by the coil itself. From transport Ic measurements on coil-shaped SDs based on a Sn10-Pb90 solder wire, we achieved a {\eta} of 79% with a {\Delta}Ic of 140 A at Hext = 500 Oe (coil #2) and a {\eta} of 84% with a {\Delta}Ic of 125 A at Hext = 530 Oe (coil #3), confirming high rectification values at large supercurrents. The large-current high-efficiency SDE in the coil-shaped SDs will be highly useful for developing the potential field of supercurrent power electronics.

Rogers and Mulders identified color entanglement as a mechanism that breaks transverse-momentum-dependent (TMD) factorization in nearly back-to-back dijet production. Using the double-Sivers asymmetry in their model, we quantify the contribution of color entanglement in the intermediate region $\Lambda_{\rm QCD}\ll q_T\ll P_T$, where $q_T$ is the transverse-momentum imbalance of the dijet and $P_T$ is the hard transverse momentum. We compare the collinear twist-three result with the TMD-factorization prediction, expressing both in terms of the Qiu–Sterman functions. In the absence of color entanglement, the factorized prediction would involve the Sivers functions of semi-inclusive deep-inelastic scattering (SIDIS). Diagrams without crossed attachments reproduce the hard coefficient obtained from the perturbative tails of these Sivers functions. Crossed diagrams, in which each coherent gluon attaches to the other hadron's quark line, contribute an extra term equal to $4/(N_c^2-1)$ times this coefficient.

Learned representations can lose latent degrees of freedom successively, suggesting a cascade of transitions whose underlying stability principle remains unclear. Here we formulate dimension-wise posterior collapse in variational autoencoder (VAE) as a fluctuation theory around partially collapsed states. Interpreting the negative evidence lower bound as an effective free energy, its quadratic expansion defines a Gaussian theory whose Hessian acts as a mass matrix for latent fluctuations. We show that the collapsed directions form an invariant fluctuation sector and derive its exact mass spectrum in terms of a conditional residual operator. A local reactivation direction lowers the free energy when the decoder variance falls below the residual spectral upper edge, with equality marking marginality. The criterion recovers principal component thresholds in the linear Gaussian VAE limit. Viewed in reverse along continuously connected branches, the reactivation boundary provides a local criterion for successive collapse. Numerical continuation experiments show successive loss of latent dimensions near these spectral marginalities. These results support a spectral cascade interpretation governed by residual information left unexplained by the surviving representation.

The Crystallography Open Database (COD) contains over half a million experimentally determined crystal structures. Validation of crystallographic data proceeds at three hierarchical levels, the third of which assesses the physical plausibility of structures. This level has typically relied on empirical heuristics or expert judgment, which are slow and error-prone given the size of crystallographic databases and the rate at which new structures are deposited. Here we assess whether universal machine-learning interatomic potentials (MLIPs) can automate this level of validation. Of the 522 086 COD entries, 317 457 (60.8%) passed a data-quality filter removing disordered structures, formula mismatches and unmodelled solvent. These structures were relaxed with M3GNet, and 314 153 (99.0%) converged without a large change in cell volume. For most entries the relaxed and deposited volumes are nearly identical. Convergence and volume change thus provide simple criteria for identifying relaxations that do not confirm the deposited structure. A manual inspection of 327 structures showed that no single descriptor threshold (energy, largest force, or atomic displacement) separates valid from invalid structures. A comparison of M3GNet, CHGNet, PET-MAD and PET-OAM on 524 selected structures revealed model-specific failures: M3GNet distorts cyclopentadienyl and other $\pi$ ligands, and both M3GNet and CHGNet distort thiophene and thiazole rings, whereas the PET models preserve these motifs. All models detected missing hydrogen atoms, and at least some detected spurious hydrogens, incorrectly assigned atom types, and two previously unreported coordinate errors. No single model detected all error types. MLIP relaxation is therefore a useful but model-dependent screening tool, and combining several models is preferable to relying on any single one.

The topological Hall effect of skyrmions is a promising electrical probe of magnetic textures, but its small magnitude limits applications. In this work, we theoretically investigate the topological Hall effect induced by sparsely distributed skyrmions in the weak-coupling limit, focusing on how the size and shape of the skyrmion affect the Hall effect. To this end, we used a formalism based on angular-momentum eigenstates, which enables systematic analysis within reasonable computation time. We found that, in clean materials where the electron mean-free path is comparable to or larger than the skyrmion size, the Hall effect depends considerably on the size and shape of the skyrmion. In particular, the Hall effect is largest when $k_F\lambda\sim 1$, and its magnitude can be tuned by the domain-wall width of skyrmions. These findings provide a basis for investigating how the shape and size of skyrmions affect transport properties and demonstrate that the topological Hall effect is controllable by engineering these properties.

Maneuver detection of non-cooperative satellites is an essential task of space situational awareness. The interacting multiple model (IMM) filter has been applied to detect unannounced maneuvers, but the standard IMM assumes a fixed Markov transition probability matrix (TPM) that must be tuned without knowledge of the maneuver rate of the target. To avoid this tuning, adaptive-TPM approaches update the TPM online from statistics computed inside the IMM. However, these statistics already depend on the TPM through the mixing step, and this dependence forms a feedback loop. Under the dynamics mismatch of orbit tracking, the loop can keep the maneuver probability high in the absence of a maneuver or suppress its rise when a maneuver occurs. In this paper, the TPM is driven by the normalized innovation squared (NIS) of a reference coast filter that is not mixed with the IMM, and the NIS is mapped continuously to the coast-to-maneuver transition probability. The reference-driven IMM (RD-IMM) is evaluated with four space-based optical sensors tracking a geosynchronous target. RD-IMM detects small burns that the fixed-TPM IMM fails to detect, with few false declarations in maneuver-free runs, and avoids both failures of the closed-loop adaptation. Moreover, RD-IMM reduces the position error after a small in-track burn by more than 50% compared with the single-filter approaches.

Conditional mutual information (CMI) probes spatial non-Markovianity and plays a central role in a recently developed framework for defining mixed-state phases based on local reversibility. This framework sharply distinguishes exponentially decaying from algebraically decaying CMI, since the latter obstructs equivalence to a state with finite Markov length. Here we show that states that flow to the same renormalization-group (RG) fixed point can nevertheless exhibit qualitatively different CMI. Starting from a critical Gibbs state of a finite-range local classical Hamiltonian, whose CMI vanishes beyond the interaction range, we show that an RG-irrelevant perturbation that breaks detailed balance generically generates algebraically decaying CMI. Crucially, these power-law tails are cutoff-suppressed: although they lead to an infinite Markov length at every fixed lattice cutoff, they vanish as a positive power of the cutoff in the continuum limit. We construct solvable models that exhibit this phenomenon and predict that the Ising-symmetric critical point of Toom's cellular automata generically exhibits such behavior. We also find analogous cutoff-suppressed CMI in the high-temperature paramagnetic phase of the long-range Ising paramagnet, in contrast with the genuine power-law CMI at the finite-temperature critical point in this same model that survives the continuum limit. We also derive a general result that in one spatial dimension, CMI decays faster than the inverse square of the buffer length if and only if the long-distance physics is Markovian.