Astrophysics of Galaxies
The ultra low-frequency spectral properties of bright extended radio galaxies in the 3CRR catalogue
J. M. Boxelaar, F. De Gasperin, M. J. Hardcastle et al. (+2 more)
Context. Active
galactic nuclei (AGN) jets are fundamental drivers of
galaxy evolution, injecting kinetic energy into their environments. The large-scale morphology and spectral properties of these
radio galaxies are consequences of complex particle acceleration, energy loss, and absorption processes. While the shape of the synchrotron spectrum encodes the
plasma's energetic history, understanding the physics of particle acceleration and duty cycles has historically been limited by a lack of well-resolved observations at ultra-low frequencies (< 100 MHz), where the oldest
cosmic ray electron populations are traced. Aims. This study aims to perform the first comprehensive multi-frequency analysis of bright extended
radio galaxies down to 58 MHz. The goal is to study electron acceleration mechanisms, accurately measure the low-frequency spectral shape, and constrain the injection index for a sample of Fanaroff-Riley (FR) I and II
galaxies using spectral ageing models. Methods. Utilising new 58 MHz observations from the LOFAR Low Band
Antenna (LBA) combined with LOFAR High Band
Antenna (HBA; 144 MHz) and Rapid ASKAP Continuum Survey (RACS, 887 MHz & 943.5 MHz & 1367.5 MHz) data, a sub-sample of 22 extended sources from the 3CRR catalogue was selected, requiring the largest angular size to be at least 2.5'. The analysis involves constructing detailed spectral index maps and utilising
radio colour-colour diagrams to interpret spectral shapes and constrain ageing model parameters across the
radio lobes. Results. This study presents the ultra-low frequency spectral index maps for this sample. For FR I
galaxies, spectral indices range from ~0.5 near the core (consistent with first-order
Fermi acceleration) to > 1.0 in the lobes. For FR II
galaxies, hotspots exhibit steep low-frequency spectra (0.5 - 0.9), suggesting complex acceleration or absorption effects.
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All authors J. M. Boxelaar, F. De Gasperin, M. J. Hardcastle, E. De Rubeis, R. J. van Weeren
Lattice Field Theory
New results on gauge field decomposition in SU(3) gluodynamics
V. Bornyakov, V. Goy and I. Kudrov
We study decomposition of the nonabelian gauge field into the Abelian component created by Abelian monopoles and the modified nonabelian components with monopoles removed after fixing the Maximal Abelian gauge in SU(3)
lattice gluodynamics. We compute the static potential V (r) for the original gauge field and for its components V_mon and V_mod at two values of the
lattice spacing. We confirm that with optimal gauge fixing the sum V_mon + V_mod deviates substantially from V(r). We show that this decomposition of the static potential is satisfied with good precision at all distances when we use another set of Gribov copies.
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Medical Physics · Cross-listed from eess.SY
Interaction Dynamics MPC for Knee Rehabilitation Exoskeletons: A Closed-Loop SEA Outer-Loop Study
Yongyan Cao and Jinshan Tang
Safe rehabilitation is an interaction-dynamics problem: the controller must regulate a prescribed motion while absorbing involuntary spasm, voluntary effort, actuator compliance, and model mismatch as disturbances. This paper instantiates the predictive interaction-dynamics framework of the base pHRI formulation on a SEA knee joint. SEA feedforward reduces the
gravity-compensated knee to the same scalar double integrator as the base framework, while a dynamic-residual measurement from spring deflection supplies an interaction-disturbance observation. A steady-state target converts the estimated disturbance into a cancelling input, and a finite-horizon quadratic program regulates deviations from that target under range-of-motion, torque, and velocity constraints. The evaluation matches stiffness and damping across controllers so gains cannot be attributed to higher impedance. Under a motion-opposing $15\unit{Nm}$ step, classical impedance and MPC without estimation produce about $500\unit{mrad}$ steady-state error, whereas Kalman-augmented interaction MPC reduces this to $1.17\unit{mrad}$ at 100~Hz and $0.70\unit{mrad}$ at 500~Hz; the 500~Hz peak is $7.27\unit{mrad}$. In 30 randomized trials, the 95th-percentile peak is $21.57\unit{mrad}$. Bounded Assist-as-Needed scheduling, a corrective-channel energy tank, constrained OSQP stress cases, direct MuJoCo execution, and a posture-clamped MyoSuite knee slice are implemented. The framework holds on a single-mass, closed-inner-loop SEA approximation; an explicit two-mass plant with a finite-bandwidth, pole-placed inner torque loop (Section~VIII) confirms this for nominal tracking but shows delivered torque can overshoot the commanded bound by 21.7% near saturation. Scope excludes clinical intent recognition, full-system passivity, safety certification, hardware trials, and multi-joint validation.
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Soft Condensed Matter
Tracking microscopic irreversibility during yielding of a colloidal fractal gel with Rheo-Echo-XPCS
William Chèvremont, Julien Bauland, Emmeline Brassac et al. (+4 more)
Understanding how microscopic structural dynamics relate to macroscopic mechanical response during yielding remains a central challenge in soft matter physics. Here, we introduce rheo-echo X-ray
photon correlation spectroscopy (rheo-echo-XPCS) with nonlinear acquisition synchronized to oscillatory shear, enabling direct measurement of irreversible nanoscale dynamics under strain amplitude control. Applying this to a carbon black colloidal fractal gel, we resolve time-periodic echoes in the vorticity-direction intensity autocorrelation function whose decay encodes non-affine structural rearrangements. We find: (i)~ballistic-like decorrelation with $\tau \propto q^{-1}$ at all strains, where the decorrelation velocity $v_\tau = 1/\langle q\tau \rangle$ scales linearly with the loss tangent $\tan\delta = G''/G'$, establishing $\tan\delta$ as a direct macroscopic signature of the rate of irreversible structural decorrelation; (ii)~functional form continuous
evolution from compressed exponential ($\alpha \simeq 1.5$) at low strain, consistent with three-dimensional dipolar strain fields in the intact network-to stretched exponential ($\alpha \simeq 0.5$) at high strain, reflecting a dimensional reduction from $d_f = 3$ to $d_f = 1$ as stress transmission shifts from bulk to quasi-one-dimensional filamentary backbones during network fragmentation.
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All authors William Chèvremont, Julien Bauland, Emmeline Brassac, Gonzalo Sanchez Vera, Stefano Aime, Frédéric Pignon, Thomas Gibaud
Mesoscale and Nanoscale Physics
Phonon polariton confinement in isotopically pure MOVPE-grown BN triangles
Maximilian Scharpey, Oskar Schröer, Daniel Wigger et al. (+5 more)
Phonon polaritons, quasiparticles formed by the resonant hybridization of light and
lattice vibrations, exhibit unique properties like the possibility of
hyperbolic dispersions. In this context, exfoliated hexagonal boron nitride (hBN) has emerged as a promising material for
phonon polariton-based research. However, to advance toward practical applications, it is essential to demonstrate efficient
phonon-polariton propagation and confinement in large-area epitaxial BN. To address this topic, we use metalorganic vapor phase epitaxy (MOVPE)-grown BN and investigate the
phonon polariton properties using scattering-type scanning near-field optical microscopy (s-SNOM) and nanoscale
Fourier transform infrared spectroscopy (nano-FTIR). We report remarkably long
phonon polariton propagation lengths, indicating the high crystalline quality of the BN layer. By using epitaxially grown isotopically pure triangular islands, we further demonstrate efficient
phonon-polariton confinement with mode patterns tunable by the incident light wavelength. Our results pave the way for implementing all-epitaxial, microscale, high-quality polariton resonators for nanophotonics and
quantum optics.
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All authors Maximilian Scharpey, Oskar Schröer, Daniel Wigger, Lena Miler, Jakub Iwański, Andrzej Wysmołek, Johannes Binder, Iris Niehues
Medical Physics
A beam–membrane biomechanical vocal fold model incorporating posturing and glottal conformation
Mohamed A. Serry, Matías Zañartu and Sean D. Peterson
The posture of the vocal folds produced by laryngeal muscle activation plays a central role in determining the dynamics of voice production. Abnormal vocal fold configurations are frequently associated with inefficient phonation and a variety of voice disorders. Although diverse glottal closure patterns have been observed clinically, the biomechanical mechanisms governing their dynamic behavior and resulting phonatory characteristics remain incompletely understood. Moreover, existing numerical models that incorporate the effects of the intrinsic musculature on posturing and glottal conformation are computationally expensive, which limits their suitability for large-scale parametric investigations. In this work, we introduce a computationally inexpensive vocal fold (VF) model wherein the body and cover VF layers are treated as a composite beam and a coupled membrane, respectively. Intrinsic laryngeal muscle activation, in addition to positioning the arytenoid cartilages and cricothyroid joint, introduces moments at the boundaries of the structure that influence glottal conformation. The model produces phonatory characteristics that are qualitatively consistent with those reported in high-fidelity finite-element models and clinical studies, thereby supporting its predictive capability while offering substantial computational advantage. The proposed framework provides biomechanical insights into the influence of incomplete glottal closure on phonation dynamics and may serve as a computationally tractable tool for investigating mechanisms underlying certain voice disorders.
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Instrumentation and Detectors
Tracking and timing measurements on irradiated TI-LGADs
A. Gomez-Carrera, L. Diehl, J. Duarte-Campderros et al. (+10 more)
Trench-isolated (TI) LGADs, developed at FBK, are pixelated LGAD implementations where pads are separated by physical trenches etched within the silicon substrate and filled with a dielectric material. Developed as a solution to the LGAD fill factor problem, this technology provides a path towards 4D tracking with reduced inefficiencies in the interpad regions. Through a dedicated 120 GeV SPS pion test beam campaign, the time resolution, efficiency, and inter-pad distance of carbon infused irradiated TI-LGADs is presented. Fluences up to 2.5$~$x$~$$10^{15}$$~$n$_{\text{eq}}$$~$cm$^{-2}$ are evaluated, for single trench implementations with varied trench width at a temperature of -25 $^o$C. The results show an interpad distance degradation with the irradiation of the detector and an optimal time resolution between 35 ps and 45 ps for all studied devices.
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All authors A. Gomez-Carrera, L. Diehl, J. Duarte-Campderros, M. Fernandez, V. Gkougkousis, B. Hiti, G. Kramberger, A. Macchiolo, Y. Padniuk, M. Puklavec, C. Torres Muñoz, I. Velkovska, I. Vila
Quantum Physics
Quantum Trajectories: Ergodicity, Perturbative Dynamics, and Stationary Response
Guocheng Zhen, Xuanrong Yang, Chengkai Zhu et al. (+2 more)
Quantum trajectories capture measurement-conditioned statistics beyond ensemble averages. For finite-dimensional Kraus dynamics, complete-reset and overlap conditions yield a unique invariant law with explicit
geometric total-variation contraction. Under finite-reference mixing and quantitative transverse contraction, $C^2$ Kraus perturbations yield two complementary stationary limits: an affine tangent law for local fluctuations and an occupation measure for rare excursions. These limits give leading observable-response formulas, including an excursion contribution at quadratic order; both limits and coefficients depend only on reference Kraus operators and their first derivatives. For Clifford-driven monitored trajectories, group structure verifies the general hypotheses and yields
geometric Wasserstein mixing uniformly over intermediate
unitaries at fixed dimensions, an equivalence between uniform total-variation ergodicity and a finite nonzero rank-one Kraus product for each fixed
unitary, and exact stationary tangent energies. Under partial measurement, tangent dynamics have almost surely finite
memory with a sharp exponential tail; every $C^2$ state observable has vanishing first-order stationary response. For weak
Hamiltonian perturbations, odd-
prime Gross–Wigner mana responds linearly in the perturbation strength $\theta$, whereas
prime-dimensional stabilizer Rényi
entropies scale as $\theta^{2\alpha}$, $\theta^2\ln(1/\theta)$, and $\theta^2$ for fixed $0<\alpha<1$, $\alpha=1$, and $1<\alpha<\infty$, respectively. Under partial measurement, the leading coefficients are strictly positive precisely for
Hamiltonians outside the real span of the measurement projectors; on this quotient, the mana coefficient defines a norm and the order-one logarithmic coefficient an explicit positive-definite quadratic form.
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All authors Guocheng Zhen, Xuanrong Yang, Chengkai Zhu, Ranyiliu Chen, Xin Wang
High Energy Astrophysical Phenomena
Simulations of 3-Dimensional Recoil Response to Coherent Elastic Neutrino-Nucleus Scattering Events in Directional Direct Dark Matter Detectors
Kwang-Chang Lai and Chung-Lin Shan
Following our earlier work on studying 3-dimensional
nuclear recoil response to
Galactic Weakly Interacting Massive Particles (WIMPs) in directional direct Dark Matter detectors, in this paper, we simulate 3-D coherent elastic
neutrino-
nucleus scattering (CEvNS) events induced by
Solar B-8
neutrinos. Our numerical results show that, in contrast to the approximately fixed patterns of the WIMP-induced signals, the characteristic ring-like angular distributions of the
nuclear recoil flux/energy of CEvNS events show clearly annual variations along the trajectories of the moving direction of incident
Solar neutrinos in different celestial coordinate systems without experimentally distinguishable target dependence.
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Mathematical Physics · Cross-listed from math.AP
A symmetry theorem for localizable steady solutions of the 3D Euler equations
Daniel Peralta-Salas and Radu Slobodeanu
A steady Euler flow is localizable if the pressure function is constant along its stream lines. This property was used by Gavrilov to construct the first smooth compactly supported steady states of 3D Euler. We prove that any analytic localizable 3D Euler flow in a bounded domain $\Omega$ is axisymmetric and $\Omega$ is a rotationally symmetric domain whose transverse section is a disk or an annulus with convex boundary curves. To the best of our knowledge, this is the first
symmetry theorem for 3D steady Euler flows. In the context of MHD
equilibria, this result shows that Grad's
conjecture holds true for
magnetic fields satisfying the isodynamic condition, a property introduced by Palumbo in the 1960's to minimize the effect of particle drifts in
plasma confinement devices.
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Quantum Physics · Cross-listed from math.NA
Reduced basis algorithm for solving nonlinear differential equations on quantum computers
Monica Lăcătuş, Matthias Möller and Sauro Succi
As
quantum computing moves toward scientific computing applications, nonlinear differential equations remain a central challenge since
quantum evolution is intrinsically linear. In this work, we introduce a reduced basis
algorithm (RBA) for
polynomial nonlinear ordinary differential equations (ODEs) and spatially discretized partial differential equations (PDEs). After time discretization, the method composes the resulting
polynomial update map over $m$ timesteps, identifies the reduced monomial basis appearing in this composed map, and constructs a linear RBA operator whose action recovers the exact $m$-timestep nonlinear dynamics. Thus, at the level of the chosen discrete update rule, the method introduces no additional approximation error beyond the time discretization error. The
qubit number requirement is governed by the size of the reduced monomial basis. For an $n$-dimensional
polynomial ODE system of degree $p>1$, the lifted register requires at most $q_m^{\mathrm{ODE}} = O(nm\log p)$
qubits in the full basis scenario. For PDEs discretized on $N^D$ grid points, a locality-based construction requires at most $q_m^{\mathrm{PDE}} = O(D\log N + n m^{D+1}\log p)$
qubits. Hence, the dependence on the grid size remains logarithmic, while the nonlinear overhead is controlled by local reduced basis size. The main computational burden is moved from the
quantum computer to a classical preprocessing step, where the reduced monomial basis and RBA operator are constructed for the chosen timestep window. Through numerical tests on the Lorenz system and the one-dimensional Burgers equation, we verify that the RBA reproduces the corresponding discrete time nonlinear dynamics exactly, while exposing the trade-off between timestep composition, reduced basis growth, and locality.
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Optics
Real-Time Visualization of the Spatiotemporal Dynamics of 3D Solitons
XinGe Liu, Chaoyang Geng, Yunhan Yu et al. (+3 more)
Three-dimensional (3D) optical
solitons bear far stronger relevance to multi-dimensional nonlinear dynamics prevalent in complex physical, chemical and biological systems than conventional 1D
solitons, and they support far richer and more intricate phenomena arising from their spatiotemporal degrees of freedom. However, real-time recording of 3D
soliton evolution with simultaneous spatiotemporal resolution remains a critical challenging. Here, we demonstrate long-term real-time visualization of 3D
soliton dynamics with spatiotemporal resolution using high-speed photodetectors combined with joint space- and time-division multiplexing. We visually capture complex transient behaviors of 3D
solitons in a multimode fiber
laser and, by integrating our method with the time-stretch technique, simultaneously record pulse-resolved beam and spectral evolutions. We observe that during the birth of 3D
solitons, the highly multimode beam stabilizes for a substantial interval prior to spectral broadening, indicating that a large number of transverse modes have already locked before longitudinal mode proliferation. These findings highlight the critical importance of real-time spatiotemporal visualization for advancing ultrafast multimode
laser design and delivering new insights into high-dimensional nonlinear dynamics.
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All authors XinGe Liu, Chaoyang Geng, Yunhan Yu, Lixia Xi, Xiaoguang Zhang, Xiaosheng Xiao
Optics
Optical Implementation of Equilibrium Propagation Using Spatial Photonic Ising Machines
Dimitri Vanden Abeele, Daniele Veraldi, Davide Pierangeli et al. (+2 more)
Equilibrium Propagation offers a compelling alternative to traditional machine learning for training energy-based networks. Here we demonstrate a hybrid optical-digital implementation of EP using a Spatial Photonic Ising Machine (SPIM). The SPIM exploits the gauge transformation method to optically encode both continuous
neuron states and rank-1 binary trainable patterns as phase modulations via a spatial light modulator, with inference realized using a finite difference scheme. The experimental system is evaluated on the Wine classification
dataset. The potential of this approach, including the use of continuous couplings and structured coupling
matrices, is evaluated numerically on the more complex MNIST
dataset. Our work provides a concrete pathway toward energy-efficient physical implementations of
Equilibrium Propagation.
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All authors Dimitri Vanden Abeele, Daniele Veraldi, Davide Pierangeli, Claudio Conti, Serge Massar
Mathematical Physics
Rapid mixing for Gibbs measures in Riemannian manifolds
Ángela Capel, Marco Castrillón-López, Sofyan Iblisdir et al. (+3 more)
Langevin dynamics on Riemannian
manifolds is analyzed. Conditions ensuring the existence of a suitable logarithmic Sobolev inequality (rapid mixing to the Gibbs measure) are identified. These conditions involve the
curvature of the
manifold, the inverse temperature, escaping directions from saddle points, and exclude barren plateaus and spurious local minima. We show that when these conditions are met, mixing times
polynomial in the dimension of the
manifold are achievable. This result is obtained through a relation between Langevin processes in the domain and in the image of a Riemannian submersion. Such a relation can be of independent interest.
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All authors Ángela Capel, Marco Castrillón-López, Sofyan Iblisdir, Angelo Lucia, Pablo Páez-Velasco, David Pérez-García
Quantum Physics
Quantum optical photoelectron interferometry
Jonathan Dubois, Viviane Cotte, Richard Taïeb et al. (+8 more)
We present a general theoretical framework for multiphoton processes driven by
quantum light fields, establishing a direct link between
photon statistics and photoelectron observables. Our results show that the autocorrelation and cross-correlation functions, which quantify the underlying
photon statistics, are directly mapped onto the resulting photoelectron spectra. Although our framework is broadly applicable, we demonstrate specifically in the example of reconstruction of attosecond beating by interference of two-
photon transitions (RABBIT) the influence of the light statistical properties. In this approach, the amplitude, contrast and phase of the oscillations of the sideband signal as a function of pump-probe delay reveal the
quantum nature of light. We analyze these observables across several
quantum configurations, including correlated infrared and harmonic modes, as well as the uncorrelated case with non-classical harmonic statistics, thereby establishing a general framework for
quantum-light RABBIT spectroscopy. We compare the analytical theory with numerical simulations for the case of classical harmonics and an infrared field in a squeezed coherent state, obtaining excellent agreement. Our results reveal how the interplay between classical and
quantum correlations dictates the coherence of the photoemission process, providing a new window into the
quantum-optical foundations of attosecond science.
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All authors Jonathan Dubois, Viviane Cotte, Richard Taïeb, Camille Lévêque, Jérémie Caillat, Pranshu Dave, Pascal Salières, David Bresteau, Charles Bourassin-Bouchet, Anne L'Huillier, David Busto
Instrumentation and Methods for Astrophysics
Japan's Possible Contributions for Coronagraph of the Habitable Worlds Observatory (HWO)
Keigo Enya, Kenta Yoneta, Naoshi Murakami et al. (+20 more)
In this paper, we describe Japan's possible contributions for coronagraph of the Habitable Worlds Observatory (HWO) based on our independent study. We are considering to contribute to the HOW coronagraph by science and hardware, based on Japan's experience for the SPICA coronagraph instrument, contributions to the Nancy Grace Roman Space
Telescope, and SCExAO for the Subaru
telescope. Currently, hardware contributions of various scales, from large-scale to small components, are considered. As an example of the large-scale hardware case, the optical and mechanical layout of the entire infrared coronagraph is presented. Several individual high-contrast technologies are also briefly introduced, for which research is ongoing in Japan. In discussions, it is pointed out that both the inner working angle (IWA) and sensitivity are particularly critical for the NIR coronagraph. In this situation, dedicated observations of a small number of targets close to the
solar system can be one of key science program in this situation, and designing consolidating science objectives, requirements, observation targets, and survey plans is important. It is essential to push the development of advanced coronagraphs that provide small IWAs. On the other hand, it is also necessary to prepare solutions that adopt more robust coronagraphs in parallel. How to coexist visible and NIR coronagraphs within constraints of volume, mass, budget etc. is an important issue. The international sharing for the coronagraph development should be carefully decided by international agreement. Although all of our studies may not be realized in contributions to the first generation of HWO instruments, we are considering Japan's multigenerational participation in the HWO to maximize outcomes of the HWO.
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All authors Keigo Enya, Kenta Yoneta, Naoshi Murakami, Jun Nishikawa, Satoshi Itoh, Taro Matsuo, Reiki Kojima, Takayuki Kotani, Olivier Guyon, Takahiro Sumi, Satoshi Miyazaki, Toru Yamada, Aoi Takahashi, Hajime Kawahara, Shota Miyazaki, Iona Kondo, Nana Higashio, Noriko Yamasaki, Masayuki Kuzuhara, Motohide Tamura, Masahiro Ikoma, Norio Narita, Julien Lozi
Optics
Polarization-controlled transport of light in a two-dimensional waveguide
J.V.S. Ferreira, A.M.G de Melo, N.A. Moreira et al. (+3 more)
Light propagation in disordered media is particularly complex due to the interference effects and polarization-mixing terms. Two-dimensional systems are particularly interesting because they feature two decoupled scattering channels, with distinct spectral statistics due to the presence of polarization-coupling terms in only one of them. We here show that in one channel, Anderson localization bounds the light transport both longitudinally and transversely. In the second channel, in contrast, diffusive transport takes place independently of scatterer density. Our results open new possibilities for engineering of light transport in two-dimensional waveguides.
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All authors J.V.S. Ferreira, A.M.G de Melo, N.A. Moreira, S.E. Skipetrov, R. Kaiser, R. Bachelard
Materials Science · Cross-listed from math.NA
Momentum Space Algorithm for Electronic Structure of Double-Incommensurate Trilayer Graphene
Ken Beard and Daniel Massatt
Numerical
algorithms for computing electronic structure of incommensurate 2D materials using ab initio models is critical for predicting material properties and guiding experiment. For
bilayers, momentum space and continuum models have been introduced to approximate observables of ab initio tight-binding models using a momenta description despite the lack of periodicity in the tight-binding model required for Bloch theory. A similar structure has been introduced for double-incommensurate trilayers using a continuum model, where the three
lattices are all mutually incommensurate. However, this description leads to a four-dimensional
lattice space, and numerical convergence of the density of states was observed to have poor convergence. In this work, we introduce a momentum space framework for double incommensurate trilayer
graphene, and introduce an efficient truncation scheme of the four-dimensional
lattice to drastically improve convergence of the density of states and momentum local density of states (a parallel object to classical band structure). We implement this
algorithm on an ab initio model of twisted trilayer
graphene and validate convergence estimates. We further verify numerically that the momentum space
algorithm, inherently higher order than the continuum model as it is an exact transformation of the tight-binding model, captures altered band behavior near the flat bands at magic angles.
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Physics and Society
Adaptive rerouting reshapes impacts of maritime chokepoint disruptions
Mitja Devetak, Jasper Verschuur and Peter Klimek
Maritime chokepoints concentrate shipping traffic. Disruptions to this traffic can have a widespread impact on the global economy. However, the way in which these impacts are shaped by the shipping sector's adaptive behavior is not well understood. Here, we introduce an empirically calibrated full-scale
agent-based model of the global commercial shipping fleet, representing 35,954 active ships moving among 1,651 ports. We use the model to quantify how rerouting changes arrival losses under chokepoint closures. Static route exposure alone does not predict realized losses. In the adaptive model, rerouting reduces losses at some directly exposed ports, while delayed vessel cycles create losses at later port calls and in dependent regions. Cumulative net shipping-day losses therefore continue to rise with closure duration because longer routes keep ships delayed after the initial adjustment. Each additional closure day reduces global shipping arrivals by 3.0% for Suez and 7.7% for simultaneous Suez, Panama, and Malacca closures. These losses are unevenly distributed in exposed regions and ports. Disruptions with known duration show different loss profiles from unexpected shocks with unknown duration, revealing that end-date information can reduce avoidable short-run losses. The results show that chokepoint risk is a dynamic problem of routing, timing, and regional exposure and not a static property of maritime-network
topology.
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Lattice Field Theory
Numerical Hints for Dyon Condensation at $\theta=2\pi$ via Wilson-'t Hooft Loops in $SU(2)$ Yang-Mills Theory
Hiromasa Watanabe, Issaku Kanamori, Okuto Morikawa et al. (+3 more)
Yang-Mills theories at $\theta$ and $\theta+2\pi$ are unitarily equivalent, but their $2\pi$ periodicity has a nontrivial realization. Recent developments in generalized
symmetries rigorously prove that confinement
vacua at $\theta=0$ and $2\pi$ should belong to different
symmetry-protected topological (SPT) states with the $1$-form center
symmetry. For its examination, we measure the Wilson-'t Hooft loop operators at $\theta=2\pi$ for the $SU(2)$ Wilson
lattice gauge action and discuss their long-distance behaviors. This requires us to identify the gauge topological charge in the presence of defects, and we employ the $1$-form covariant DBW2 gradient flow to smear
lattice gauge fields. We find a clear perimeter-law signal for the dyonic Wilson-'t Hooft loop at $\theta=2\pi$, providing numerical evidence in the pure $SU(2)$ Yang-Mills theory for the theoretically expected dyon condensation at $\theta=2\pi$.
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All authors Hiromasa Watanabe, Issaku Kanamori, Okuto Morikawa, Yuki Nagai, Yuya Tanizaki, Akio Tomiya
Materials Science
Dopant-induced modifications of the optical properties of GaSe
Jakub Sójka, Katarzyna Olkowska-Pucko, Kacper Walczyk et al. (+5 more)
Doping plays a crucial role in tailoring the electronic, optical, and
magnetic properties of
semiconductors, enabling control of carrier dynamics and the formation of functional states for optoelectronic applications. We investigate the influence of Fe dopants on the optical properties of GaSe
crystals using photoluminescence (PL) spectroscopy under varying excitation power, temperature, and
magnetic field. Fe incorporation introduces multiple sharp emission lines in addition to intrinsic excitonic transitions, including free and localised
excitons. Power- and temperature-dependent measurements indicate that these emission features are associated with Fe-related dopant centres (Fe-bound
excitons). Magneto-PL measurements reveal two distinct families of $g$-factors, enabling the identification of intrinsic excitonic transitions and Fe-induced defect states. These results demonstrate that Fe doping creates optically and magnetically active centres in GaSe, providing insight into defect-related excitonic processes and their potential relevance for magneto-optoelectronic and
quantum photonic applications.
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All authors Jakub Sójka, Katarzyna Olkowska-Pucko, Kacper Walczyk, Zakhar R. Kudrynskyi, Volodymyr Boledzjuk, Adam Babiński, Maciej R. Molas, Grzegorz Krasucki
Quantum Physics
Quantum Statistical Memory Advantage Reveals Predictive Structure in Chaotic Invariant Measures
Maida Wang, Xiao Xue, Minh Chung et al. (+1 more)
Long-horizon prediction of a chaotic system is governed by fidelity to its invariant measure, and which parts of that measure a learned predictor needs is a physical question not known in advance. We establish a
quantum statistical
memory advantage for interrogating it. A
quantum statistical prior (Q-Prior), trained once on classical data, stores an efficiently preparable $k$-point marginal in polynomially many
circuit parameters against exponentially many for explicit tabulation. Collective Bell measurements on two copies then estimate any post hoc Pauli-expectation magnitude at a copy cost independent of register size, with a worst-case exponential separation from single-copy protocols. A single Bell
dataset supports an entire family of candidate observables at a cost growing only logarithmically in the family size, so an exponentially large candidate space stays open for later analysis. We implement the protocol on IQM superconducting processors with two-copy registers of up to 54 physical-
qubit chips. We apply this to turbulent channel flow and ERA5
forecasting, resolving invariant structure by statistical sector and order. Turbulent phase correlations persist through eighth order, while most predictive gains arise from low-order constraints; in ERA5, planetary-wave phase coherence complements covariance regularisation, identifying distinct low-order sectors with predictive value.
Quantum statistical
memory is therefore both a near-term computational resource and an instrument for identifying which invariant structures matter for prediction.
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All authors Maida Wang, Xiao Xue, Minh Chung, Peter V. Coveney
Materials Science
The phase composition and physical properties of melt-quenched multicomponent alloy FeCoNiB0.7Si0.3Be
Oleksandr I. Kushnerov, Sergey I. Ryabtsev, Pavlo O. Galagan et al. (+1 more)
The structure and physical properties of the high-
entropy multicomponent
alloy FeCoNiB0.7Si0.3Be in the as-cast and melt-quenched states were studied. The cooling rate of the melt-quenched films was estimated to be approximately 10^6 K/s based on the film thickness. X-ray analysis revealed a multiphase structure, including a BCC-type ordered phase (structural type B2) and intermetallic compounds (Fe, Ni, Co)2B. In melt-quenched samples, the fraction of the B2 phase increased, leading to a decrease in microhardness from 10400 MPa in the as-cast state to 8900 MPa in the melt-quenched state.
Magnetic studies confirmed the
ferromagnetic nature of the FeCoNiB0.7Si0.3Be
alloy. The coercive field of melt-quenched samples (17500 A/m) was significantly higher than that of the as-cast ones (5200 A/m), which is attributed to structure refinement and an increased level of microstresses.
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All authors Oleksandr I. Kushnerov, Sergey I. Ryabtsev, Pavlo O. Galagan, Valerij F. Bashev
Nuclear Theory
Transport simulations with a constrained momentum-dependent chiral mean-field equation of state at various isospin fractions
Jan Steinheimer and Marcus Bleicher
We present a comparison of the UrQMD model using a
chiral mean field EoS (CMF) with flow and pion production data in heavy ion collisions at low beam energies $E_{\mathrm{lab}}=0.2-2.0 A$ GeV and varying iso-
spin fraction. The CMF model parameters are constrained by known properties of the high density equation of state of QCD at varying iso-
spin fractions. This allows us to calculate the equation of state as well as
nuclear interactions for different physical systems like
neutron stars and heavy ion collisions in a consistent way. It is found that heavy ion reactions at the upcoming FAIR facility will only have marginal sensitivity on the iso-
spin dependence of the high-density equation of state. At lower beam energies, comparing to FOPI, HADES and S$\pi$rit data, the sensitivity is higher but the observed deviations and systematic uncertainties of the existing data are larger than the sensitivity to the
symmetry energy.
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Materials Science
Physics-informed time-series forecasting of perovskite photoluminescence stability
Alexander Wieczorek, Manuel Kober-Czerny, Fábio Lopes et al. (+5 more)
Accelerated ageing using elevated temperatures and illumination is one of the most common methods to rapidly study the stability of novel
semiconductor materials. However, as the pace of materials discovery continues to accelerate, even faster stability evaluations are needed. A physics-informed time-series
forecasting algorithm designed to predict the long-term photoluminescence stability of metal halide perovskites is presented. A diverse experimental
dataset of 167 metal halide perovskites is collected, including different crystallinities and compositions. These are stressed using heat and light, while the photoluminescence (PL) is monitored. The >86k collected PL spectra are featurized using a physics-informed model, and a hybrid CNN-LSTM model is trained to forecast the PL intensity during degradation of samples unseen during model training. Notably, the approach generalizes across the material groups and outperforms baseline
benchmarks. Furthermore, the physics-based featurization ensures explainability, enabling analysis to identify critical stability descriptors for given predictions. It is expected that this approach will be adapted to other types of time-series data and enables a pathway to significantly reduce experimental testing times.
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All authors Alexander Wieczorek, Manuel Kober-Czerny, Fábio Lopes, Austin George Kuba, Leon Müller, Christian M. Wolff, Jason Hattrick-Simpers, Sebastian Siol
Exactly Solvable and Integrable Systems
Volterra-Bogoyavlensky lattices and solutions of $A_{2n}^{(1)}$ invariant Painlevé equations
Y. F. Adans, H. Aratyn, J.F. Gomes et al. (+1 more)
The objective of this work is to develop a framework that exploits the
lattice structure of the $k$-th Volterra–Bogoyavlensky equations ($k\in\mathbb N$, $k>1$) to generate rational solutions of higher symmetric Painlevé equations. For $k=2$, we show that the Volterra
lattice, equipped with suitable initial conditions, exactly models the one- and two-dimensional orbits generated by half-translation operators of the $A_2^{(1)}$ symmetric Painlevé IV equations. This correspondence yields explicit closed-form expressions for all solution components in terms of generalized Okamoto
polynomials and leads to new algebraic recurrence relations among these
polynomials. We present two generalizations of the above Volterra
lattice. One is derived from a fractional translation of the $A_{4}^{(1)}$ symmetric Painlevé equations. It generalizes Volterra
lattice structure in the multi-component setup of the affine $A_{4}^{(1)}$ group and it is shown to generate solutions of the $A_{4}^{(1)}$ symmetric Painlevé equations from the seed solution invariant under dihedral group $D_{5}$. The other is the $k=3$ Bogoyavlensky
lattice structure. It satisfies recurrence relations that naturally extend recurrence relations of the Volterra
lattice. These results shed light on connection between Volterra–Bogoyavlensky
lattices, dihedral
symmetries, and rational solutions of higher Painlevé systems.
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All authors Y. F. Adans, H. Aratyn, J.F. Gomes, G.V. Lobo
Quantum Physics
Kerr-induced nonreciprocal transparency and group delay in a hybrid cavity magnomechanical system
M. Amghar, N. Chabar, M. Amazioug et al. (+4 more)
We propose a scheme for realizing nonreciprocal transparency, Fano resonances, and slow/fast light in a hybrid cavity magnomechanical system containing two YIG spheres and a mechanical resonator. The nonreciprocal behavior originates from the
magnon Kerr nonlinearity, which induces direction-dependent frequency shifts and modifies the interference pathways among cavity
photons,
magnons, and
phonons. We show that the hybrid system supports multiple transparency windows arising from
magnon- and magnomechanical-induced interference processes. The Kerr interaction strongly reshapes these transparency features, producing asymmetric Fano resonance line shapes and enabling controllable nonreciprocal transmission. Furthermore, the associated dispersion exhibits pronounced directional asymmetry, leading to
giant differences in the group delay for opposite propagation directions and allowing reversible switching between slow- and fast-light regimes. We investigate the roles of hybrid coupling strengths and dissipation channels and identify parameter regimes where the nonreciprocal response is maximized. These findings establish Kerr-engineered magnomechanical systems as promising platforms for integrated nonreciprocal microwave photonics and
quantum information technologies.
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All authors M. Amghar, N. Chabar, M. Amazioug, R. Altuijri, A. N. Al-Ahmadi, R. Ahl Laamara, A. Abdel-Aty
High Energy Physics (Phenomenology)
Subtraction of infrared divergences in light-quark QCD sum rules
Ding-Kun Lian, Jin-Peng Zhang, Zi-Xi Ou-Yang et al. (+4 more)
In QCD sum rules for light-
quark systems, infrared (IR) divergences can appear in the Wilson coefficients of certain condensates. These divergences manifest explicitly in the coordinate-space expressions of the light-
quark propagators. We propose an improved method to eliminate these IR divergences at the propagator level and present a subtraction formula that implements this procedure. Compared to the existing methods that rely on the mixing between
quark and
gluon condensates of the same dimension to eliminate IR divergences, this method is more intuitive and easier to apply in practical QCD sum rule calculations.
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All authors Ding-Kun Lian, Jin-Peng Zhang, Zi-Xi Ou-Yang, Qi-Nan Wang, Hua-Xing Chen, Wei Chen, Jia-Jun Wu
High Energy Physics (Phenomenology)
Decays of heavy scalars in the Grimus-Neufeld model
Aurimas Vitkus, Simonas Draukšas and Thomas Gajdosik
We consider an extension of the Standard Model by an additional
Higgs doublet and a Majorana
neutrino, which we call the Grimus-Neufeld Model (GNM). For certain parameter choices the GNM can be compared to the Inert Doublet Model (IDM), which has a scalar dark matter candidate. This motivates that the scalars of the GNM could possibly contribute to dark matter. To check this, we present the tree-level two-body decays of the heavy scalars of the GNM and compute the lifetime of the pseudoscalar in the IDM limit.
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Quantum Physics
Characterizing the functional role of quantum coherence in energy transfer
Hallmann Óskar Gestsson and Alexandra Olaya-Castro
Quantum coherence has been suggested to play a role in excitation energy transfer in open
quantum systems, yet a quantitative approach to assessing its influence on the transfer process is still missing. Using Nakajima-Zwanzig projection operators, we derive a general
memory kernel identity that enables us to characterize and quantify the impact of coherence in the eigenenergy basis on a generalized rate of energy transfer. Applying our approach to the electronic dynamics of a dimer coupled to a structured
phonon bath, we demonstrate how
quantum coherence acts to modulate energy transfer.
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