Biological Physics · Cross-listed from q-bio.PE
A multiscale theory based on metabolic scaling connects forest dynamics to tree-size distributions
Christian Grilletta, Tommaso Anfodillo, Gaia Pasqualotto et al. (+4 more)
Scaling relations linking species size, abundance, and resource availability are among the most robust empirical regularities in ecology. However, a mechanistic explanation for how these community-level laws emerge from ecological processes remains elusive. Here, we address this gap by developing a minimal spatially explicit dynamical framework for forest communities that incorporates seed dispersal, growth limited by local light availability, local competition, and global resource constraints grounded in metabolic scaling principles. By deriving an analytical solution for the tree-size distribution, we show that its stationary state exhibits two distinct power-law regimes whose exponents are controlled by the relative strength of resource and spatial competition. The crossover between these regimes is set by the interplay between seed injection and local resource availability, establishing an explicit link between the scaling exponent of the size distribution and forest condition. Finally, we show that boundary disturbances can break the ecological balance between competing species and induce effects that propagate deeply into the forest bulk, far beyond the single-plant dispersal range. Together, these results provide a unifying dynamical perspective on forest scaling laws with potential applications to a broad range of biological communities.
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All authors Christian Grilletta, Tommaso Anfodillo, Gaia Pasqualotto, Samir Suweis, Andrea Rinaldo, Amos Maritan, Davide Bernardi
Astrophysics of Galaxies
Classifying Quasar Types Without a Spectrum
Adrien Hélias, Pauline Barmby, Sarah C. Gallagher et al. (+2 more)
Distinguishing between Type 1 and Type 2
quasars is important because it helps us understand
accretion regimes, black hole mass scaling, disk instabilities and feedback processes in active
galaxies. Although spectroscopy provides robust classification, it does not scale well with the millions of
quasars observed in modern surveys, as it requires substantial time and resources to acquire a good spectrum. On the photometry side,
quasar light curves are always irregularly sampled and affected by the specifics of photometric surveys, making them difficult to analyze. In this work, we show that we can use irregularly sampled light curves from the Zwicky Transient Facility to classify
quasar types without a spectrum, using Slepian Wavelet Variance. This technique allows us to decompose the variance of light curves into multiple timescales. We use agglomerative hierarchical clustering to classify 516 Type 1 and 238 Type 2
quasars from the MILLIQUAS catalogue, solely based on their wavelet variance curves. We obtain a recovery rate of 99% for Type 1 and 87% for Type 2
quasars, and the few misclassified
quasars show the opposite variability behaviour to their spectral type. In contrast to structure functions and the Damped Random Walk model, Slepian Wavelet Variance offers a complementary, model-independent view of variability across short and long timescales.
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All authors Adrien Hélias, Pauline Barmby, Sarah C. Gallagher, Shahram Abbassi, Matthew J. Graham
Materials Science
Resonant Raman signatures of bright and momentum-dark exciton coupled by intervalley phonon scattering in monolayer WSe2
Hendrik Lambers, Nihit Saigal, Lara Blinov et al. (+3 more)
Exciton-
phonon coupling in atomically thin transition metal dichalcogenides governs key processes such as
exciton thermalization and intervalley scattering and remains challenging to access directly by optical spectroscopy. Here, we employ resonance Raman spectroscopy at cryogenic temperatures to probe
exciton-
phonon coupling in hBN-encapsulated WSe_2 monolayers. Tuning the excitation
laser across the bright
exciton X_KK resonance, we observe rich Raman spectra and focus on the resonance profile of the degenerate A_1'/E' optical
phonon mode. The profile exhibits two asymmetric resonance peaks whose energetic separation significantly exceeds the
phonon energy - a feature that cannot be explained by first-order Raman scattering alone. We demonstrate that this discrepancy is resolved by including third-order Raman scattering, in which intervalley scattering enabled by a finite-momentum
phonon couples the bright
exciton X_KK to a momentum-dark
exciton X_d. Fitting the experimental resonance profiles of two independent samples with a model comprising coherent first- and third-order scattering yields consistent
exciton energies and linewidths, with a momentum-dark
exciton X_d approximately 45meV to 55meV below the bright
exciton X_KK. The results indicate efficient bright-to-dark
exciton coupling. Our findings provide a microscopic framework for understanding the anomalously bright emission spectra of WSe_2 monolayers despite its
spin-forbidden lowest
exciton transition and highlight the role of momentum-dark
excitons in resonant light-matter interaction.
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All authors Hendrik Lambers, Nihit Saigal, Lara Blinov, Jonas Kiemle, Alexander W. Holleitner, Ursula Wurstbauer
Quantum Physics
Hamilton-Zero: A Neural Tensor-Network Foundation Model for Ground States of Arbitrary Quadratic Qubit Hamiltonians
Timothy Heightman, Elena Orlova, Philip Mantrov et al. (+1 more)
A central promise of useful
quantum advantage is the ability to compute ground states of
Hamiltonian systems beyond the reach of classical simulation methods. Here we demonstrate that this problem can be effectively amortized across an arbitrary and universal set of
Hamiltonians by a foundation model with $\sim0.5$B variational parameters, trained with contemporary techniques from large
language models and deep reinforcement learning. To do this, we formulate $\text{spin-}1/2$
quantum ground-state learning as
manifold variational optimisation over centrally odd scalar functions on $\mathrm{SU}(2)^N$. This replaces explicit
Hilbert-space vector amplitudes with
manifold functions on which the
Hamiltonian acts through Lie derivatives, evaluated by custom automatic differentiation primitives. We prove that the resulting variational principle on this
manifold preserves the $\text{spin-}1/2$ sector's ground-state upper bound using the Peter-Weyl
theorem and justify the choice of such a representation with a no-go
theorem for pure state foundation NQS. We then pre-train our foundation model on a
dataset of hundreds of thousands of different
Hamiltonian systems, varying the connection
topology, system size, interaction types and strengths, bringing together a century of many-body literature. Using a novel $\mathrm{SU}(2)$ replica-exchange Langevin sampler and sharded natural-gradient optimisation, we train our model with our own extension of the Kronecker-Factored Approximate
Curvature (KFAC) optimiser on system sizes up to 64
qubits. On a held-out generalisation
dataset, we fine-tune our model on system sizes of up to 1024
qubits, and evaluate on systems up to 8100
qubits.
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All authors Timothy Heightman, Elena Orlova, Philip Mantrov, Aleksei Ustimenko
Materials Science
Magneto-optical magnetoelectric voltage sensor
Michael P. Path and Jeffrey McCord
Applications in high-voltage and electromagnetically harsh environments require reliable galvanically isolated voltage sensing, which can be achieved using optical readout. While established optical voltage sensors rely on electro-optic effects or piezoelectric strain with direct optical detection, strain-mediated magnetoelectric coupling combined with magneto-optical readout offers an alternative voltage sensing principle that remains largely unexplored. Here, such a sensor based on a bismuth-substituted yttrium iron garnet magneto-optical indicator film mechanically coupled to a piezoelectric actuator is presented. Voltage induced stress results in changes of the out-of-plane magnetization via magnetoelastic coupling which is detected through magneto-optical Faraday rotation. A critical state of the domain structure is set via an applied bias field, in which voltage-induced nucleation and domain-wall motion dominates the response. In this high sensitivity regime, both AC and DC voltage readout modes are demonstrated, based on either voltage-driven magnetization reversal or voltage-induced modifications of the magnetization loop shape. Equivalent voltage noise densities in the millivolt per root hertz range are achieved. The results establish strain-mediated magneto-optical voltage sensing as a distinct approach to optically isolated voltage measurement.
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Solar and Stellar Astrophysics
1.5D investigation of the Hanle effect in the Ca I 4227 line using partial frequency redistribution. Comparison of synthetic Stokes profiles in Bifrost and MURaM-ChE rMHD models
Devang Agnihotri, L. S. Anusha, D. Przybylski et al. (+2 more)
Modeling scattering polarization in the Ca I 4227 Å line is important for diagnosing chromospheric
magnetic fields. We investigate the relative influence of formation heights and
magnetic fields, through the Hanle effect, on spatially averaged synthetic Stokes profiles using realistic
solar atmospheres. We employ 1D vertical columns from 3D radiative magnetohydrodynamic simulations of the
solar chromosphere performed with the Bifrost and MURaM-ChE codes, and solve the 1.5D non-local thermodynamic
equilibrium polarized radiative transfer equation including partial frequency redistribution and the Hanle effect. The intensity profiles from both simulations agree at line center, while MURaM-ChE exhibits enhanced wing intensity due to deeper, hotter formation regions. The polarization signals form at greater heights in MURaM-ChE than in Bifrost. In the non-
magnetic case, Bifrost produces stronger line-core polarization, whereas MURaM-ChE shows enhanced wing polarization. Including the
magnetic fields from the simulations results in stronger Hanle depolarization of <Q>/<I> in Bifrost. The distinct thermal and
magnetic structures at the corresponding formation heights therefore produce significantly different polarization profiles. In particular, the Hanle signatures suggest that the line-core formation region in MURaM-ChE is less strongly magnetized than that in Bifrost.
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All authors Devang Agnihotri, L. S. Anusha, D. Przybylski, R. H. Cameron, S. K. Solanki
Superconductivity
Spin-polarized supercurrents and Josephson diode effect in altermagnets
Janus F. Niebuhr, Matthias Eschrig and Danilo Nikolić
We present a systematic theoretical study of the Josephson effect in junctions consisting of a d-wave altermagnet (AM) placed between two BCS
superconductors (SC). In general, the SC/AM interfaces are
spin-active and modeled by
spin-dependent $\delta$ potentials, allowing for an arbitrary direction of the local exchange field vector. The model is formulated within the fully
quantum (Gor'kov) and quasiclassical (Eilenberger) Green's function technique, applied to two distinct cases of (i) a weakly
spin-polarized AM (exchange field much smaller compared to the
Fermi energy) and (ii) a strongly
spin-polarized AM (exchange field comparable to the
Fermi energy). We apply our model to the SC/AM/SC geometry, accounting for the Josephson current-phase relation (CPR). In the weakly
spin-polarized regime, the CPR displays the normal Josephson effect. Irrespective of the orientation of the altermagnet, the junction undergoes the $0-\pi$ transition. Depending on the orientation, the system displays the features similar to those of a
ferromagnetic or an
antiferromagnetic junction. To investigate the
spin-polarized currents and nonreciprocal transport as the central results of the present work, we put the main focus on the strongly
spin-polarized regime. Within this regime, we distinguish two cases. A coplanar exchange field profile across the junctions displays the normal Josephson effect; however, with a pure and stable long-range second harmonic in the CPR. In contrast, a noncoplanar exchange field profile gives rise to the so-called
quantum geometric phases across the junction, leading to the absence of the phase-inversion center in the Josephson CPR. As a result, a Josephson diode effect emerges with a significant charge diode efficiency larger than 30% and a perfect
spin diode efficiency of 100%.
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Earth and Planetary Astrophysics
Three new exoplanet systems from the Dispersed Matter Planet Project
J.R. Barnes, C.A. Haswell, Z.O.B. Ross et al. (+7 more)
We present a radial velocity analysis of three bright, low-activity
stars identified by the Dispersed Matter
Planet Project (DMPP). We use a
Bayesian framework to compare purely Keplerian models with models incorporating
stellar activity via a quasi-periodic Gaussian Process (GP). DMPP-7 (HD 118006) is a slightly evolved
star that harbours a single 0.72 Saturn-mass
giant ($m_\textrm{p}\sin i$ = 69 M$_\oplus$) with an orbital period of P = 4.93 d. A longer 21 d - 22 d period cannot be conclusively confirmed as a
stellar rotation signature rather than a purely Keplerian signal. For HD 67200, which exhibits Ca ii H&K variability, a model with only a GP is strongly favoured over a purely dynamical model. The GP model shows moderate evidence for a single Keplerian with P = 2.67 d. For HD 2134, a 21 d - 32 d rotation period signal is associated with tentative FWHM variability. A model with a GP is not conclusively favoured, but all models considered show moderate evidence for an additional single Keplerian with P = 2.78 d. Despite our target selection favouring near edge-on orbital geometries, we find no evidence for transits in TESS photometry. DMPP-7 b lies at the transition between the high-radius population and the Neptunian ridge and savannah regions. Further observations are required to establish whether the coherent short-period HD 67200 and HD 2134 signals are
stellar or dynamical in origin. If planetary, the signals correspond to minimum masses of $m_\textrm{p}\sin i$ = 2.07 M$_\oplus$ and $m_\textrm{p}\sin i$ = 2.86 M$_\oplus$
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All authors J.R. Barnes, C.A. Haswell, Z.O.B. Ross, E. Rutherford, M.R. Standing, A.T. Stevenson, D. Staab, L. Fossati, J.S. Jenkins, D. Alves
General Relativity and Quantum Cosmology
Static multipolar Einstein-vector-Gauss-Bonnet black holes
Burkhard Kleihaus and Jutta Kunz
We construct and analyze static multipolar black holes in Einstein-vector-Gauss-Bonnet theory with a quadratic coupling function. The vectorized solutions bifurcate from the Schwarzschild black hole at discrete values of the Gauss-Bonnet coupling, obtained from a perturbative
eigenvalue problem on the Schwarzschild background and labelled by the angular multipole number $\ell$. We restrict to the fundamental radial branches. The electric sector contains the known spherically symmetric $\ell=0$ branch as well as axisymmetric branches with $\ell>0$. These electric branches extend to larger values of the coupling. The
magnetic sector features a sequence of axisymmetric branches, including the previously found
magnetic dipole branch at $\ell=0$. The
magnetic branches instead exist only on finite intervals of the coupling, ending at critical solutions. Away from the bifurcation point, nonlinearities generate additional multipoles, but even-$\ell$ and odd-$\ell$ moments remain separated.
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Materials Science
Strain-controlled sign reversal of the anomalous Hall effect in Ru/[Co/Ni]$_N$ multilayers
Jingying Zhang, Sigang Wang, Yue Xiang et al. (+4 more)
The anomalous
Hall effect (AHE) is a hallmark transport phenomenon in ferromagnets arising from relativistic
spin-orbit interaction. Here, we report an unexpected sign reversal of the AHE in Ru/[Co/Ni]$_N$ multilayers controlled by the stacking sequence of the Ru layer. When Ru is placed beneath, rather than atop, the Co/Ni multilayers, the anomalous
Hall signal switches from positive to negative. By systematically varying the multilayer repeat number N and combining transport measurements with first-principles calculations, we show that this reversal originates from in-plane tensile strain imposed by the Ru underlayer, which reshapes the electronic structure and redistributes Berry
curvature near the
Fermi level. Our findings establish interfacial strain as an effective knob for tuning Berry-
curvature-driven transport and suggest a pathway toward strain-controlled topological transport phenomena in
magnetic multilayers.
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All authors Jingying Zhang, Sigang Wang, Yue Xiang, Wenhui Xie, Zhe Yuan, Yi Liu, Zongzhi Zhang
Solar and Stellar Astrophysics
First and Comprehensive Study of V0757 Pup : $\gamma-$Doradus Pulsator in Detached Eclipsing Binary
Bakuh Danang Setyo Budi, Bryant Randolph, Rafa Nanda Akilah et al. (+3 more)
Pulsating
stars in detached eclipsing binary (EA) systems are known for providing many important physical informations which constrain both
stellar structure and
evolution theories. To date, fewer than 50 $\gamma$ Doradus (GDOR)
stars have been found in eclipsing binary systems, making them important targets to study g-mode pulsation inside the
stars. We present a comprehensive physical and pulsational analysis of V0757 Pup (TIC 6939791), a detached eclipsing binary system observed by the TESS mission (Sectors 7, 34, 61, and 88) and followed up with ground-based spectroscopy from the Thai National
Telescope. By combining light curve modeling with radial velocities derived from medium-resolution spectra, we determined the fundamental
stellar and atmospheric parameters with high precision. The system consists of an F2V primary ($M_1=1.305\pm0.026M_\odot, R_1=1.643\pm0.020R_\odot$) and a G1V secondary ($M_2=0.934\pm0.030M_\odot, R_2=0.941\pm0.079R_\odot$). We performed a detailed frequency analysis of the residual light curves, identifying two dominant independent pulsation frequencies at $f\sim0.79$ c/d and $0.98$ c/d. These frequencies, along with the derived pulsation constant ($Q\sim0.6$ d), confirm the primary component as a $\gamma$ Doradus pulsator. An analysis of Eclipse Timing Variations (ETV) reveals non detection of third body companions with current available
dataset, strengthen by the result of
Gaia astrometric analysis. Evolutionary modeling indicates the system is $\sim2.2$ Gyr old, with the primary expected to fill its Roche lobe in $\sim1$ Gyr. Additionally, we calculate a distance of $d\approx350$ pc based on orbital and SED modeling, which is in excellent agreement with the
Gaia DR3 parallax distance.
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All authors Bakuh Danang Setyo Budi, Bryant Randolph, Rafa Nanda Akilah, Evan Irawan Akbar, Hakim Luthfi Malasan, Puji Irawati
Quantum Physics
The optimization landscape of peaked-circuit generation
Ilyes Jamoussi
Peaked
circuits are random
quantum circuits whose measurement returns one bitstring far more often than chance. The probability of that string is the peakedness, and a verifier who knows the string checks the device in a few shots. Peaked
circuits are a candidate route to verifiable
quantum advantage, and classical generation is the bottleneck. Aaronson and Zhang train a variational
circuit by gradient descent, and the peakedness they reach decays exponentially with the number of
qubits. They state that either their optimizer stalls or no efficient generation method exists. Here we show that no bare fixed base fits the decay we measure and that neither the barren plateau nor fragmentation of the solution set explains it. We measure the optimization landscape on eighteen instances per size, from eight to sixteen
qubits, under a protocol whose falsifiers were fixed in advance. The decay steepens as the
qubit number grows, leaving extrapolations to larger devices unsupported. A better optimizer exists, but it gains a few percent and the peakedness it reaches decays at nearly the same rate. Aaronson and Zhang attribute the difficulty to a barren plateau. The plateau is present, but the second-order amplitude data are depth-independent while the attained peakedness is not. Independent runs land on uncorrelated solutions, yet paths connecting them stay well above the scale of a random state, so fragmentation fails at that scale. In the deep limit we take the scrambled state Haar-random. There we prove that no search over a
polynomial-parameter Lipschitz family, exhaustive search included, beats the scale of a random state by more than a poly(n) factor on average. Both branches of the Aaronson-Zhang alternative therefore stay open. A generation method must beat a preregistered baseline, and a hardness argument must accommodate a solution set connected at the scale of a random state.
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Optics
Metastable soliton necklaces confined by the boundary of a flattop region
Dmitry A. Zezyulin
We present quasistationary ring-shaped
soliton necklaces in a two-component envelope propagating in a medium with competing cubic-quintic nonlinearity. Metastable propagation of
soliton necklaces results from a balance of repulsion between adjacent out-of-phase
solitons in one component and confinement by the boundary of a flattop region in the other. Numerical simulations demonstrate metastable propagation over about a hundred diffraction lengths, even with random noise added to the input envelopes. The maximum number of
solitons in metastable necklaces can be controlled either by changing the size of individual
solitons or by adjusting the width of the flattop region hosting the necklace.
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Quantum Physics
CoQui: A Coordinate-Conditioned Quantum Implicit Generative Adversarial Network for End-to-End Image Generation
Xue Yang, Rigui Zhou, ShiZheng Jia et al. (+7 more)
Quantum generative
adversarial networks (QGANs) have attracted increasing
attention for image generation using parameterized
quantum circuits. Existing amplitude-based approaches face two key limitations: pixel locations are typically encoded by computational-basis indices or address
qubits, causing
quantum resources to grow with image resolution; meanwhile, jointly decoding many pixels from normalized
quantum states introduces probability competition among pixels and limits precise pixel-wise control. To address these issues, we reformulate
quantum image generation as coordinate-conditioned implicit function learning. Our method takes spatial coordinates and latent variables as inputs, uses a classical
embedding network to generate input-dependent
circuit parameters, and evaluates a variational
quantum circuit at each coordinate. Pixel intensities are directly obtained from the expectation value of a dedicated color
qubit, and a complete image is generated by querying all spatial coordinates. This design decouples image resolution from address-
qubit requirements and avoids shared probability-normalization constraints across pixels. We further design a specialized variational
quantum circuit to provide structural inductive bias for coordinate-conditioned generation. Simulated experiments on two
benchmark datasets show that our method outperforms FRQI-based generation and PQWGAN in visual and quantitative quality while using fewer
qubits, and also achieves better generation quality than the corresponding classical baseline.
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All authors Xue Yang, Rigui Zhou, ShiZheng Jia, Dax Enshan Koh, Siong Thye Goh, Young-Wook Cho, YaoChong Li, Xuezhi Ma, Hongyu Chen, Xin Wang
Earth and Planetary Astrophysics
Chemical Tracers for 3D Atmospheric Asymmetries on WASP-69 b
Nidhi Bangera, Ludmila Carone, Vikas Soni et al. (+6 more)
Warm
giant exoplanets exhibit strong three-dimensional temperature contrasts that can significantly alter atmospheric chemistry through quenching and photochemistry, yet transmission spectra are commonly interpreted using one-dimensional, limb-averaged models. Such simplifications may bias inferred atmospheric properties, particularly
metallicity and C/O ratio. In this work we investigate the relative influence of atmospheric composition and three-dimensional thermal structure on atmospheric chemistry and transmission spectra using WASP-69b as a test case. WASP-69b is a ~900K warm Saturn, residing in a thermal regime especially sensitive to disequilibrium chemistry. We use three-dimensional general circulation model derived pressure-temperature profiles as inputs for a one-dimensional photochemical-kinetics model to resolve longitudinal and latitudinal chemical asymmetries across the atmosphere. We find that CH4 exhibits strong latitudinal variations linked to deep quench temperatures, while SO2 shows longitudinal asymmetries driven by upper-atmospheric photochemistry and irradiation geometry. In contrast, CO2 remains comparatively insensitive to spatial thermal variations and emerges as a robust tracer of atmospheric
metallicity. Synthethic transmission spectra reveal that three-dimensional chemical asymmetries can produce spectral variations comparable to those induced by
metallicity itself, demonstrating that limb-averaged interpretations can mask substantial spatial structure in warm
giant exoplanet atmospheres.
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All authors Nidhi Bangera, Ludmila Carone, Vikas Soni, Kenneth Goodis Gordon, Luca Fossati, Helena Lecoq-Molinos, Paul B. Rimmer, Peter Woitke, Christiane Helling
Soft Condensed Matter
Density-Selected Topological Pathways in the Melting of Single-Particle-Thick Stripes
José Rafael Bordin
The melting of stripe-forming systems involves changes in connectivity that are not fully captured by conventional structural and orientational descriptors. We investigate a two-dimensional model with competing interactions whose low-temperature phase consists of one-particle-thick stripes. Molecular dynamics simulations along seven heating isochores are analyzed using thermodynamic, orientational, dynamical, and graph-based observables. Heating produces a multistage reconstruction in which the loss of stripe
alignment and the reorganization of filament connectivity occur over distinct temperature ranges. Density controls whether the disordered filaments fragment into finite
polymer-like clusters or remain joined in a dynamically fluid, system-spanning network. The topological observables distinguish these outcomes, which are not resolved by the thermodynamic and orientational responses alone. Thus, the same ordered stripe microphase can melt into topologically distinct fluids selected by density.
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Soft Condensed Matter
Magnetic active matter across scales
Francisca Guzmán-Lastra, Margaret Rosenberg, Marco Musacchio et al. (+2 more)
Magnetic interactions provide a versatile and powerful tool for controlling and organizing active matter, where individual units continuously consume energy to drive autonomous motion. These interactions arise naturally in biological systems, such as magnetotactic bacteria, and can be engineered into synthetic platforms, including colloidal microswimmers,
magnetic nanoparticles, and macroscopic granular
robots. This review focuses on active, self-propelled particles that carry an intrinsic
magnetic dipole moment, powered by their own energy consumption rather than driven by external fields; here, the dipole moment mediates interactions and self-organization, not propulsion. We survey experimental and theoretical studies across all length scales, showing how dipolar interactions shape single-particle dynamics, collective behavior, and self-organization. We discuss models incorporating pairwise dipolar forces and confinement, and examine emergent phenomena such as chaining, swarming, and tunable pattern formation. We close by outlining challenges and opportunities in the design, control, and application of
magnetic active systems, from programmable materials and biomedical actuation to nonequilibrium physics.
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All authors Francisca Guzmán-Lastra, Margaret Rosenberg, Marco Musacchio, Lorenzo Caprini, Hartmut Löwen
Quantum Physics
Limitations on Joint Coherence Transfer in Quantum Thermodynamics
Piotr Ćwikliński and Michał Studziński
Coherences between different energy levels are strongly constrained by thermodynamics. Here we ask whether several coherence transfers that can be optimized separately can also be optimized simultaneously by the same thermodynamic process. Using an energy-resolved Stinespring representation of thermal operations, we express elementary transfer amplitudes as inner products of bath-weighted vectors. Joint saturation imposes collinearity and phase-closure conditions on these vectors, which must all arise from one energy-preserving system–bath
unitary. This gives necessary compatibility conditions for arbitrary finite-dimensional
Hamiltonians. We show that joint incompatibility persists in a system with both degenerate and nondegenerate energy levels: rigorous computer-assisted semidefinite-program bounds, combined with explicit thermal constructions, prove that three individual thermal optima cannot be approached simultaneously. We then determine how well different coherences can be protected when their optima are incompatible. For a four-level family at infinite temperature, we obtain the complete closed retention region and the cost of balancing the coherences relative to their individual optima. At positive temperature, covariance and Gibbs preservation permit joint retention that no thermal operation can approach. Finite-bath constructions and certified semidefinite relaxations bound the balanced thermal performance. When two coherences carry independent phases, these bounds describe simultaneous preservation of interference visibility and phase Fisher information.
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High Energy Physics (Phenomenology)
Higgs Mass and CP violating Phases Implications on the SUSY Breaking Scale in MSSM
Tarek Ibrahim and Anas Zorik
The large
Higgs mass $m_h \approx 125 GeV$ can raise the values of the SUSY breaking parameters in the Minimal Supersymmetric Standard Model MSSM to the range of several TeV scale. The CP violating phases in the MSSM can induce EDMs of the
fermions in the theory already in conflict with the current experimental upper limit unless the masses of the SUSY partners are on the heavy side. We invistigate the implications of both constraints, the
Higgs Mass and the complete set of SUSY CP violating phases in the analysis of the electric dipole moments EDMs on the SUSY breaking parameters and thus on the SUSY mass spectrum. We use the electric dipole moments of the electron, the
neutron and the
proton as our probes in this study.
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Instrumentation and Methods for Astrophysics
SPORE: An Event-Level Sampling Pipeline for Multi-Telescope Neutrino Astronomy
Jeffrey Lazar, Perrine Wilmet and Gwenhaël de Wasseige
We present an open-source Python package for simulating
neutrino events from astrophysical point and extended sources using tabulated instrument response functions (IRFs). The package encodes three detector response components - effective area, point spread function, and energy resolution - in a selection-agnostic HDF5 format, which can represent a
neutrino telescope whose response is supplied in that form, whether from a public release or a private study. Sampling
algorithms cover point sources (inverse-CDF with Poisson or fixed-count modes), extended sky distributions (hierarchical inverse-CDF sampling, including full RA- and declination-dependent flux maps), and multi-detector joint analyses. We validate the framework via a round-trip consistency test using the publicly available IceCube 10-year tracks data release: the released IRFs are ingested into the package and used to generate a synthetic event set, whose declination distribution reproduces the observed one to 10-15% across the northern sky. The reconstructed-energy distribution agrees to within about a third over the bulk of the sample but exceeds the data by up to a factor of three below 600 GeV, a discrepancy we trace to the coarse true-energy binning of the public smearing
matrix rather than to the sampling: an independent forward fold of the same IRFs reproduces it. We further compare against the IceCube HESE 7.5-year public data release: the sampled deposited-energy spectrum tracks the published best-fit expectation, and the observed data fall within the goodness-of-fit distribution built from 1,000 sampled pseudo-experiments, though on its well-fitting side, as expected for an expectation that was itself fit to those data.
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Optics
Programmable vs. Static Beam Shaping in Ultrafast Laser Micromachining: A Critical Review
Krystof Kobliha and Peter Hauschwitz
Beam shaping has become one of the principal determinants of throughput, precision, and process robustness in ultrafast
laser micromachining. Despite this, the field is still largely interpreted through a historical distinction between programmable and static optical elements, a framework that increasingly fails to explain recent advances. This review reexamines that perspective and argues that beam shaping should instead be understood as a hardware-
algorithm co-design problem. Across high-power spatial light modulators, machine-learning holography, hybrid optical architectures, and massively parallel processing, recent advances converge on the same conclusion: performance depends more on the codesign of optical hardware and computational
algorithms than on any individual optical component. To establish a common basis for comparison, seven beam-shaping technologies and five
algorithm families are evaluated within a unified seven-axis framework spanning optical performance, programmability, computational cost, and industrial deployment. This analysis identifies where the long-standing trade-off between throughput and flexibility has genuinely disappeared. In industrial parallel ablation and high-throughput two-
photon polymerisation, programmable devices now sustain average powers once reserved for static optics, demonstrating why hardware-centred comparisons no longer capture the state of the art. Beyond reviewing recent developments, this work provides a predictive design framework for the next generation of beam-shaping systems. It introduces a benchmarking methodology, practical technology-selection criteria, measurable research milestones, and a reporting standard for improving comparability across future studies.
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Optics
Two-Stage Deformable-Convolutional Inverse Design of Nanophotonic Absorbers from Optical Spectra
Waleed Waseer, Muhammad Shahid Jabbar, Muhammad Sohail Ibrahim et al. (+1 more)
Data-driven inverse design enables efficient generation of nanophotonic structures with prescribed optical responses, but spectrum-to-geometry mapping remains challenging due to non-uniqueness and fine
geometric features. This work presents a two-stage deformable-convolutional framework for reconstructing metal–
insulator–metal resonator geometries from 80-dimensional absorption spectra. The spectrum is projected to a $150\times4\times4$ latent representation and decoded into a $64\times64$ resonator mask. Training combines supervised reconstruction with least-squares
adversarial refinement initialized from the best supervised checkpoint. A three-run ablation compares deformable convolution with plain convolution, involution, Dynamic Conv, and ODConv under the same architecture. The proposed model achieves $20.79\pm0.31$~dB PSNR and $0.8501\pm0.0082$ SSIM, improving over plain convolution by 2.16~dB and 0.0831, respectively. It further achieves Dice $0.9623\pm0.0027$, IoU $0.9342\pm0.0038$, and boundary F-score $0.9550\pm0.0027$. Spectral consistency evaluated using a frozen forward surrogate yields RMSE $0.0805\pm0.0013$ and $R^2=0.7923\pm0.0065$. Learned offsets show stronger adaptive sampling at coarse and intermediate decoder stages. Overall, deformable sampling with supervised initialization and
adversarial refinement improves spectrum-conditioned geometry reconstruction.
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All authors Waleed Waseer, Muhammad Shahid Jabbar, Muhammad Sohail Ibrahim, Shujaat Khan
Mesoscale and Nanoscale Physics
Quantum Anomalous Hall Effect in $d^{10}$ Oxide Monolayers
Zeyu Li, Xudong Zhu, Yulei Han et al. (+1 more)
Quantum anomalous
Hall effect (QAHE) arises from the interplay between
magnetic order and
spin-orbit coupling, which opens up a topologically nontrivial band gap to host
chiral edge states in the absence of
magnetic field. So far,
magnetic order of QAHE usually originates from partially filled transition-metal $d$ orbitals or correlation-driven moiré bands. Here, we propose an experimentally accessible family of two-dimensional
oxides, M$_2$DO$_6$ (M = Zn, Cd; D = Se, Te), that can realize QAHE from the half-filled O-$2p$ orbital induced spontaneous ferromagnetism. In M$_2$DO$_6$ monolayers,
spin-polarized Dirac points appear at K/K$^{\prime}$ valleys and along $\Gamma$-K/$\Gamma$-K$^{\prime}$ lines. $C_3$ rotational
symmetry then generates eight
symmetry-related crossings in the first Brillouin zone. Upon gap opening by
spin-orbit coupling, each massive Dirac point contributes half Chern number, resulting in a high-Chern-number QAHE phase with $\mathcal{C}=4$. We establish cation deintercalation as a general strategy to activate O-$2p$ ferromagnetism in
oxides. Our finding provides a route to realize QAHE from O-$2p$ ferromagnetism and offers design principles applicable to oxygen-based
magnetic topology platforms beyond conventional $d$-electron systems.
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All authors Zeyu Li, Xudong Zhu, Yulei Han, Zhenhua Qiao
Solar and Stellar Astrophysics
Results from the first spectropolarimetric survey of $\gamma$ Dor pulsators
J. Labadie-Bartz, R. Ouazzani, C. Neiner et al. (+8 more)
Context.
Magnetic fields can have an important influence on
stellar structure and
evolution. In intermediate-mass (A- and F-type)
stars, there are many known
stars with directly measured strong, globally organized
magnetic fields, as well as indications of weak and/or small-scale variable fields. However, among the intermediate-mass $\gamma$ Dor pulsators, there are no known
stars with strong surface
magnetic fields. Aims. The broad goal of this work is to search for evidence of strong, globally organized fields at the surface of $\gamma$ Dor pulsators. Methods. We identified objects consistent with being $\gamma$ Dor pulsators based on an analysis of space photometry from the Transiting
Exoplanet Survey Satellite (TESS) mission. A spectropolarimetric survey was then conducted on a subset of 47 of these objects, with a precision sufficient to detect dipolar surface
magnetic fields down to a threshold of about 10 – 100 G. Results. We detected strong magnetism in three targets. However, upon closer inspection, none of these appear to be genuine $\gamma$ Dor pulsators. We found no evidence of surface magnetism in any of the remaining 44 objects. Conclusions. We conclude that either strong, globally organized
magnetic fields and $\gamma$ Dor pulsation are mutually exclusive, or that such
stars are exceedingly rare. A possible explanation is that strong global fields inhibit the excitation mechanism, which prevents $\gamma$ Dor pulsations from being driven in strongly
magnetic intermediate-mass
stars. The dipolar surface
magnetic field strength upper limits we derive for this sample ($\lesssim$ 50 – 100 G) provide valuable constraints for surface boundary conditions for asteroseismic models that include magnetism for $\gamma$ Dor
stars.
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All authors J. Labadie-Bartz, R. Ouazzani, C. Neiner, V. Antoci, P. Stanley, T. Natan, K. Thomson-Paressant, S. D. Chojnowski, B. Mas Sanz, O. Dürfeldt Pedros, V. Petit
General Relativity and Quantum Cosmology
Taiji Resolving Power for the Transverse Scalar Mode of Gravitational Waves
Bo-Xuan Ge and Zhoujian Cao
We investigate how small a co-propagating transverse-scalar component can be resolved by Taiji in an already identified bright tensor chirp. Using a source-tracked tensor-null response, we formulate the problem in terms of the minimum resolvable scalar strain fraction and evaluate it over the sky. For a one-year
benchmark chirp with tensor signal-to-noise ratio $\rho_T=1000$, we find that Taiji can rule out transverse-scalar strain fractions $\epsilon_b\gtrsim0.532\%$ at the all-sky median level. The threshold scales as $\epsilon_{b,\min}\propto\rho_T^{-1}$, so brighter tensor events can probe correspondingly smaller scalar fractions. We further find that this sub-percent resolving power remains predictable under small source-parameter mismatches through the associated tensor-leakage structure.
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Soft Condensed Matter
Effect of Weak Non-Conservative Dynamics on Pattern Formation in Scalar Active Matter
Sameer Kumar
Biological systems such as bacteria and
cells undergo growth or degradation, resulting in weak violations of mass conservation. We investigate how such weak non-conservative dynamics affect phase separation in scalar active matter by incorporating a reaction term into a minimal continuum model. Through numerical simulations and linear stability analysis, we show that even weak non-conservative reactions arrest coarsening and stabilize nonequilibrium microphase-separated states. With increasing activity, the system undergoes a morphological transition from interconnected labyrinthine patterns to worm-like structures and eventually to isolated droplets. Quantitative analysis of the correlation function and static structure factor reveals a well-defined steady-state characteristic length. Qualitative analysis of the resulting phases shows that the non-conservative reaction primarily promotes microphase separation and enhances local hexagonal ordering, while activity predominantly controls the domain morphology. Our results demonstrate that weak violations of mass conservation fundamentally alter the nonlinear coarsening dynamics of active phase separation and provide a minimal framework for understanding pattern formation in related systems.
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Quantum Physics
Uniformly Stable Minimal Weyl–Heisenberg Measurements Approaching the SIC Benchmark
Xiuwu Zhu and Yu Wang
Informational completeness (IC) guarantees that an inverse exists, not that it is statistically well conditioned. For minimal rank-one Weyl–Heisenberg (WH) measurements, covariance makes the nonidentity projector-Gram spectrum proportional to the fiducial's ambiguity intensities, with
eigenvalues \(d|\chi_\phi(u)|^2\), turning stability into an explicit worst-direction design problem; write \(\lambda\) for its smallest nonidentity
eigenvalue. Haar fiducials are IC almost surely while \(\mathbb E[\lambda^{-1}]=\infty\), and an explicit
geometric family used to establish balanced informationally complete measurements in every dimension has a normalized spectral floor bounded above by an exponentially decaying envelope. We then construct a hierarchy of minimal measurements. A cyclic family with exactly \(d^2\) outcomes in every integer dimension has floors \(\Theta(d^{-3})\) for odd \(d\) and \(\Theta(d^{-5})\) for even \(d\); a finite-field family for \(q=2^m\) obeys the uniform bound \(\lambda\ge4/9\). Our main result treats every
prime-power dimension of characteristic \(p\ge5\). A balanced one-coordinate perturbation repairs the zero ambiguity axis of a cubic Alltop state, gives an attained floor uniformly bounded below by a positive constant, and confines the entire nonidentity spectrum to \([L_q,U_q]\) with \(U_q/L_q\to1\). Its SIC-normalized minimum tends to one, and \(\lambda(\phi_q)/\Lambda_q^\star\to1\) for the global finite-field WH max–min optimum \(\Lambda_q^\star\), without assuming SIC existence. The complete spectrum determines the exact finite-sample
Hilbert–Schmidt error of canonical linear inversion at \(I/d\), while its lower edge controls local Fisher efficiency and canonical-shadow bounds.
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Mathematical Physics
A uniform elliptic reduction, an order-matching criterion, and precision benchmarks for the strong-coupling Birman-Schwinger analysis of the lattice three-boson trimer
Mikhail Dolgopolov
We present a rigorous strong-coupling Birman-Schwinger analysis of the three-
boson lattice Schroedinger operator on Z^2 at the exceptional quasimomentum K = pi. First, we provide an exact closed-form
benchmark for the fiber Fredholm determinant, valid for every quasimomentum K, obtained via a uniform
elliptic reduction. Second, we formulate and prove a general order-matching criterion determining whether a leading-order Fredholm determinant asymptotic, with relative error O(1/mu), suffices to fix the constant-order additive energy correction, or if the next-order refinement is required. Applying the criterion to the formal branch z = -2mu + d, we identify an algebraic crossing -2mu + 6 + 8/mu + O(mu^{-2}), but demonstrate that this crossing does not correspond to a true
eigenvalue of the full
Hamiltonian. The actual ground state obeys the rigorous variational bounds -3mu <= z_1^{pi,s}(mu) <= -3mu + 6, so that z_1^{pi,s}(mu) = -3mu + O(1), the same leading branch as at K = 0; direct finite-volume diagonalisation confirms the refined asymptotic -3mu + 6 + O(mu^{-1}) and spectral gap 2mu - 2 + O(mu^{-1}). We independently confirm that the known K = 0 constant C approximately 3.96458 requires no analogous refinement. Finally, we compare the asymptotic precision levels achieved across recent
lattice few-body models and draw a structural parallel with the parity-based classification of topological band
insulators at time-reversal-invariant momenta.
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Materials Science
Optically Tunable Threshold Switching and Thermally Activated Transport in Planar Ag/MAPbI$_3$ Thin Single-Crystal Devices
Ofelia Durante, Valeria Demontis, Sebastiano De Stefano et al. (+14 more)
Halide perovskites have enabled major advances in optoelectronics, extending well beyond photovoltaics. Their mixed ionic-electronic conduction, once regarded as detrimental to device stability, is increasingly viewed as a functional degree of freedom for
memory and neuromorphic-inspired devices, especially when coupled to external stimuli such as light. Specifically, single
crystals are attractive models because they suppress grain-boundary effects and microstructural disorder that can mask intrinsic transport and interfacial mechanisms in polycrystalline films. Here, we report the growth of thin methylammonium lead iodide (MAPbI$_3$) single
crystals by a space-confined method and their integration into planar two-terminal devices with directly deposited Ag contacts. At room temperature, the devices exhibit ultra-low dark currents ($10^{-13}-10^{-12}$ A) and negligible hysteresis in the dark. Under illumination, the current increases due to photogeneration and the I-V characteristics develop a pronounced polarity-dependent hysteresis and a threshold-like transition between two conductance states. Temperature-dependent dark measurements (300-400 K) show thermionically activated, contact-influenced transport and a weakly varying normalized hysteresis metric. Together with the back-to-back Schottky-diode analysis and control devices using more inert contact materials, these results support a transport model in which Ag/perovskite interfaces play a central role and the hysteretic response is influenced by coupled interfacial and ionic processes.
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All authors Ofelia Durante, Valeria Demontis, Sebastiano De Stefano, Selene Matta, Adolfo Mazzotti, Daniela Marongiu, Emanuele Meloni, Elisa Pili, Fang Liu, Nicola Sestu, Angelica Simbula, Mauro Carta, Michele Saba, Andrea Mura, Massimiliano Di Ventra, Giovanni Bongiovanni, Antonio Di Bartolomeo
Solar and Stellar Astrophysics
Statistics of Solar Filament Mass based on CHASE Sun-as-a-star Spectroscopic Observations
T. Y. Xie, Z. H. Zhao, X. Cheng et al. (+5 more)
Filaments are cool and dense
plasmas suspended in the hot corona of the Sun and other
stars. Accurately estimating their masses is of great significance for understanding subsequent eruptions and induced space weather effects, but it remains hindered by their intrinsic
geometric uncertainties, particularly in spatially unresolved
stellar observations. To test and calibrate the methods for estimating the masses of
stellar filaments, we conduct a statistical Sun-as-a-
star analysis of
solar filaments, utilizing full-disk H$\alpha$ spectroscopic observations from the Chinese H$\alpha$
Solar Explorer (CHASE). A total of 1346 filaments, covering a period from January 2024 to October 2025, are identified via a machine-learning
segmentation model. We construct their virtual sun-as-a-
star spectra by spatially integrating the filament regions and then obtain their optical parameters by cloud-model fitting. Upon correcting projection effects, we establish a representative three-dimensional morphological scaling of length, apparent width, and line-of-sight depth ($L:W_{\rm app}:D_{\rm LOS} \approx 4.5:1:1.7$), with a median filament depth of about 8000 km. Interestingly, the Sun-as-a-
star estimated mass shows high consistency with the resolved intrinsic mass across the full sample, with a log-space regression slope of 1.07. As the first large-sample Sun-as-a-
star study of
solar filaments, our results provide empirical constraints on filament geometries and masses, offering a critical reference for estimating
stellar filament masses based on H$\alpha$ spectroscopy.
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All authors T. Y. Xie, Z. H. Zhao, X. Cheng, Y. H. Chen, Z. Zheng, Q. Hao, C. Li, M. D. Ding