Pattern Formation and Solitons
Self-similar vector solitons for the coupled higher-order nonlinear Schrodinger equations in inhomogeneous optical fibers
Houria Triki and Vladimir I. Kruglov
We prove the existence of two kinds of self-similar vector
solitons in an inhomogeneous optical fiber medium, where light propagation is governed by a pair of coupled higher-order nonlinear Schrodinger equations with varying second- and third-order dispersions, self- and cross-phase modulation non linearities, self-steepening, and linear gain/loss effects. The newly found self-similar waves comprise bright-W-shaped and kink-antikink waveforms with nonvanishing amplitudes. As a practical exam ple, we discuss the propagation dynamics of these
soliton structures in a periodically distributed fiber system as well as an exponential dispersion-decreasing fiber. The results demonstrate that the parameter functions of gain/loss and third-order dispersion serve as a key factor in determining the nonlinear dynamics of self-similar vector
solitons. In particular, we find that precise control over the shape and dynamic
evolution of self-similar pulses can be achieved through a proper choice of the distributed third-order dispersion parameter, while the gain/loss coefficient controls their intensity.
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Mathematical Physics · Cross-listed from math.AP
Modified wave operators for nonlinear Schrödinger equations in the full subcritical long range regime
Jia Shen and Yifei Wu
We construct modified wave operators for the nonlinear Schrödinger equation $i\partial_tu+\frac12\Delta u=|u|^pu$ in the full subcritical long-range case $0<p<2/d$, with small, nonvanishing, analytic final data $W(x)$ with bounded logarithmic gradients. Previous results established large-time asymptotics for selected classes of Cauchy data. Moreover, the exact asymptotic expansion for $p<1/d$ remained unknown. When $1/d<p<2/d$, our result gives the approximation $$\frac{1}{(it)^{\frac{d}{2}}} e^{\frac{i|x|^2}{2t}} W\left(\frac{x}{t}\right) \exp\left[ -i\frac{t^{1-\frac{dp}{2}}-1}{1-\frac{dp}{2}} \left|W\left(\frac{x}{t}\right)\right|^p \right]$$ The wave operator is constructed by an iteration in the analytic spaces with decreasing radius. When $p\le 1/d$, we construct the profile from a finite truncation of a Fuchsian equation coupled with a transport equation. This profile still leaves a long-range triangular coupling whose terminal integral does not preserve the required fast decay class. The construction yields quantitative $L^q$ asymptotics for $2\le q\le\infty$ and uniqueness in the prescribed analytic asymptotic classes. The central new ingredients are a nonlinear final-state normal form that removes this long-range coupling and a mixed iteration in particular analytic spaces.
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Astrophysics of Galaxies
SPURS: An Ultra-deep View Inside the Compact, Nitrogen-Enriched Nuclei of Little Red Dots
Mengtao Tang, Daniel P. Stark, Charlotte A. Mason et al. (+7 more)
We present the first ultra-deep rest-UV spectroscopy of four UV-bright Little Red Dots (LRDs), obtained from the SPURS Cycle 4 Large Program. The spectra reveal broad CIV (FWHM $\approx2700-2800$ km s$^{-1}$) in two LRDs, alongside narrow-line densities elevated above
star-forming
galaxies ($n_e\sim10^4-10^5$ cm$^{-3}$, reaching $10^6$ cm$^{-3}$ in the most extreme source) and nitrogen-enhancements in all four LRDs. We detect broad HeII emission (FWHM $\approx930$ km s$^{-1}$) in one LRD, and two others with fast P-Cygni absorption ($\gtrsim2200$ km s$^{-1}$). Strong interstellar absorption lines and Ly$\alpha$ damping wings reveal the UV continuum is deeply embedded in neutral gas ($N_{\rm HI}\gtrsim10^{22}$ cm$^{-2}$) in all four LRDs. Detections of fluorescent FeII and OI emission and fine-structure absorption indicate this gas lies close to the UV-emitting region. In archival $z>4$ samples, we find nitrogen and strong CIII] emission are significantly more common in LRDs than in the
galaxy population. The transmission of broad CIV, tracing the broad-line region or cocoon, depends on rest-optical color within our sample, consistent with an orientation-dependent picture in which bluer, less obscured sightlines offer a more direct, polar view of the central engine and its
outflows. We find several potential signatures of very massive
stars, whose winds may contribute to nitrogen enhancement. We investigate other abundance patterns expected from supermassive
stars but our results are inconclusive. Our results place the UV-emitting region within $\lesssim8$ pc of the LRD
nucleus, consistent with an actively assembling
nuclear star cluster. Dynamical interactions in this extremely dense environment, including
tidal disruption of
stars, may explain the high incidence of nitrogen enhancements in LRDs.
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All authors Mengtao Tang, Daniel P. Stark, Charlotte A. Mason, Zuyi Chen, Tucker Jones, Sarah Searle Grannis, Peter Senchyna, Lily Whitler, Keerthi Vasan G. C., Viola Gelli
Quantum Physics
Bargmann Invariants Are Insufficient for Complete Local-Unitary Orbit Discrimination
Lin Zhang and Bing Xie
Bargmann invariants constructed from a bipartite density operator and its two lifted marginals are
polynomial invariants of local-
unitary conjugation. We determine the precise information encoded in these invariants. Whenever one subsystem is a
qubit, the ordinary marginal-word family determines the full spectrum of the partial transpose and hence decides whether the state has the positive-partial-transpose property. In $2\otimes2$ and $2\otimes3$ systems, this yields complete separability criteria. For the two-
qubit system, a finite subfamily additionally separates local-
unitary orbits, and a finite extension generates the
polynomial invariant ring. These three tasks already diverge for
qubit-qutrit states: we exhibit full-rank, locally maximally mixed states that agree on all ordinary marginal-word invariants yet have different operator-Schmidt ranks, together with a quartic correlation invariant that separates them. When both local dimensions are at least three, the analogous collapse on the locally maximally mixed sector produces isospectral pairs consisting of one separable state and one entangled state with negative partial transpose. The ordinary Bargmann
algebra therefore coincides with the full local
unitary invariant ring if and only if both subsystems are
qubits. The missing data are
geometric: they encode the placement of global eigenspaces relative to the tensor-product decomposition
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High Energy Physics (Theory)
Detecting one-dimensional bosonic SPT phases via twisted entropic order parameter
Kosei Fujiki, Tsubasa Oishi and Soichiro Shimamori
Entanglement asymmetry, introduced by F. Ares, S. Murciano and P. Calabrese, provides a density-
matrix diagnostic of
symmetry breaking and successfully captures the Landau data associated with a broken
symmetry pattern. However, it is by now well established that gapped
quantum many-body systems can exhibit phases which are not characterized solely by Landau
symmetry breaking. A fundamental example is a
symmetry-protected topological (SPT) phase, and the ordinary definition of
entanglement asymmetry is insensitive to this topological information. In this work we introduce a refined quantity, which we call the twisted entropic order parameter, designed to detect SPT phases from reduced density
matrices, particularly focusing on one-dimensional bosonic systems. The key ingredient in our construction is an ancilla degrees of freedom that coherently records the untwisted state and the twisted state associated to a one-ended topological defect of unbroken
symmetry, so that the enlarged density
matrix retains the charge carried by the defect endpoint. We demonstrate our proposal in concrete
lattice models and further generalize it beyond ordinary group
symmetries, establishing its ability to diagnose SPT phases. This provides a first step toward a unified
entanglement-asymmetry framework for diagnosing
quantum phases of matter.
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Quantum Physics
Coherent Floquet quantum reservoirs for molecular property prediction
Luofei Wang, Da Zhang, Congren Wang et al. (+5 more)
Quantum reservoir computing (QRC) uses
quantum dynamics to represent input histories for prediction through a trained classical readout. Discrete time
crystals (DTCs) exhibit robust subharmonic responses under periodic driving, and previous work has used their dynamics to construct DTC-QRC. Here we construct a DTC-based reservoir architecture to predict molecular properties from structural and dynamical observations. Coherent Floquet
evolution processes local molecular graph events and surface-hopping frames, while controlled reset regulates the contribution of earlier inputs. Measurements at the end of each input sequence yield a feature vector of fixed dimension. Trained classical decoders use this vector for inhibitor-activity and blood–
brain-barrier permeability classification and electronic-gap
forecasting, while the reservoir parameters remain fixed during training. With matched input lengths and output widths, DTC-QRC outperforms echo-state networks on long-prefix graph classification and the studied ethene gap
forecasting tasks. Dephasing lowers performance in both applications, consistent with a role for coherent propagation. Experiments on the Quafu superconducting
quantum cloud platform show that pair observables retain task information under device noise. The architecture provides a common framework for molecular screening and time-resolved property prediction using
quantum reservoir computing.
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All authors Luofei Wang, Da Zhang, Congren Wang, Yiming Li, Yuxiao Yang, Xuan Zhang, Xuefeng Cui, Zhang-Qi Yin
High Energy Astrophysical Phenomena
Evidence for the binary nature of the long-period radio transient ASKAP/DART J1832-0911
Csanád Horváth, Natasha Hurley-Walker, Ziteng Wang et al. (+2 more)
Long-period transients are a class of periodic pulsed
radio source repeating on the minute to hour timescale. Recently, an increasing number of them are being identified as binary systems, specifically white
dwarfs with low-mass main-sequence companions. In this work we analyse the most luminous long-period transient discovered to date, ASKAP/DART J1832-0911, with two years of
radio data, and propose that it, too, may be a white
dwarf system, although in a far more compact orbit than the aforementioned. The pulses are composed of quasi-periodic components which evolve in a systematic way over days and months. The source is highly linearly or elliptically polarised and its brightness enabled very high signal-to-noise measurement of the time-resolved Faraday rotation measure, which was found to vary across pulse phase. The linear polarisation position angle, circular polarised fraction, and spectral index also varied systematically in ways not typical of
pulsars and magnetars. We show that an ultra-compact asynchronous polar explains much of the phenomenology of ASKAP/DART J1832-0911, in particular the
evolution of the pulse morphology, rotation measure variation, and periodic X-ray emission, although we cannot conclusively prove a binary nature. However, our model makes testable predictions.
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All authors Csanád Horváth, Natasha Hurley-Walker, Ziteng Wang, Andrew Zic, Emil Lenc
High Energy Physics (Experiment)
Search for the process $e^+e^-\to f_1(1285)$ at the SND detector
SND Collaboration, M. N. Achasov, A. E. Alizzi et al. (+42 more)
In the experiment with the SND detector at the VEPP-2000 $e^+e^-$
collider, a search is performed for the direct production of the $C$-even $f_1(1285)$ resonance in $e^+e^-$ collisions. The analysis is based on data with an integrated luminosity of about 200 pb$^{-1}$, accumulated in the center-of-mass energy range of 1.14–1.46 GeV, of which about 72 pb$^{-1}$ were recorded near the maximum of the $f_1(1285)$ resonance. The $f_1(1285)$ production cross section at the resonance maximum $\sigma(e^+e^-\to f_1)=(31\pm 13\pm 2)$ pb and the branching fraction $B(f_1(1285)\to e^+e^-)=(3.5\pm 1.4\pm 0.3)\times 10^{-9}$ have been measured. The significance of the observation of the $e^+e^-\to f_1(1285)$ process is $2.5\sigma$. Since the significance is low, we also present the upper limits at the 90% confidence level: $\sigma(e^+e^-\to f_1)<48\mbox{ pb}$ and $B(f_1(1285)\to e^+e^-)<5.4\times 10^{-9}$.
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All authors SND Collaboration, M. N. Achasov, A. E. Alizzi, A. Yu. Barnyakov, E. V. Bedarev, K. I. Beloborodov, A. V. Berdyugin, D. E. Berkaev, A. G. Bogdanchikov, A. A. Botov, D. E. Chistyakov, T. V. Dimova, V. P. Druzhinin, R. A. Efremov, L. V. Kardapoltsev, A. S. Kasaev, A. A. Kattsin, V. R. Khamidullin, A. G. Kharlamov, I. A. Koop, A. A. Korol, D. P. Kovrizhin, A. S. Kupich, A. P. Kryukov, A. R. Mamedov, N. A. Melnikova, N. Yu. Muchnoi, A. E. Obrazovsky, A. A. Oorzhak, I. V. Ovtin, E. V. Pakhtusova, I. A. Polomoshnov, K. V. Pugachev, S, A. Rastigeev, Yu. A. Rogovsky, V. A. Romanov, S. I. Serednyakov, D. A. Shtol, Z. K. Silagadze, K. D. Sungurov, I. K. Surin, Yu. V. Usov, V. N. Zhabin, V. V. Zhulanov
Cosmology and Nongalactic Astrophysics
(Re)constructing Accurate Axion Oscillations
Hoang Nhan Luu and Chanda Prescod-Weinstein
The cosmological
evolution of ultralight
axions typically involves rapid oscillations on the timescale of the inverse mass, making it challenging to resolve the dynamics at both the background and perturbation levels. In this study, we numerically implement a novel approach to this problem based on an effective field theory (EFT) – that is, for the first time, capable of reconstructing the relativistic oscillations intrinsic to the
axion field. Compared to other available techniques, the reconstruction of the rapid oscillations is unique to the EFT approach, which describes the
axion effective field through a wavefunction representation with relativistic corrections, rather than through effective fluid variables. From a computational standpoint, our approach archives a high level of accuracy – up to a subpercent agreement with the exact solution – while remaining relatively fast compared to alternative methods. As such, it opens up new possibilities for high-precision predictions for
axion searches with future cosmological experiments.
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Cosmology and Nongalactic Astrophysics
A Tale of Two Gauges: Effective Field Theory for Relativistic Behavior of Cosmological Axions
Hoang Nhan Luu and Chanda Prescod-Weinstein
In this work, we present a formalism to model the relativistic behavior of
axions. The relativistic behavior of
axions is surprisingly difficult to model precisely, as it involves oscillations on timescales much shorter than the Hubble timescale. To overcome this challenge, one typically resorts to some form of effective treatment, focusing only on the time-averaged description of the exact oscillations. Salehian, Namjoo & Kaiser provide a systematic framework for such treatment, based on the effective field theory formalism. While the aforementioned study was formulated for
axion perturbations in the Newtonian gauge with no anisotropic stress, we extend the formalism to the synchronous gauge that is more conventionally used for numerical implementation in a realistic cosmological setting. Unlike their work, however, we propose a fluid interpretation in which the
axion field can be identified as a perfect fluid at all times, both in the exact and effective regimes. Moreover, we present the effective field theory for the Newtonian gauge with non-zero anisotropic stress, making the original formulation more general and useful for scenarios where the matter content of the universe is multi-component. These results lay the theoretical foundation for a companion paper where we discuss how the
axion field should be incorporated alongside other species in common cosmological Boltzmann solvers.
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Solar and Stellar Astrophysics
Uncovering the Origin of Slow Rotators among Intermediate-Mass Stars in the Star-Forming Cluster Trumpler 14
Khushboo K. Rao, Wen-Ping Chen, Hsiang-Yu Chen et al. (+2 more)
Intermediate-mass (about 1.5-8 M$_{\odot}$)
stars exhibit a wide range of rotation rates and have gained
attention for their roles in the extended main-sequence turnoffs (eMSTO) seen in some young and intermediate-age clusters (ages $< 2$ Gyr). Although rapid rotation is expected due to their radiative envelopes, the presence of slow rotators remains puzzling. In this study, we examine disk and X-ray signatures among the intermediate-mass members of the
star-forming cluster Trumpler 14. Of the 118 intermediate-mass members, 24 are considered disk-bearing on the basis of their infrared spectral indices derived from spectral energy distributions. The majority of these reside outside the heavily irradiated cluster core and are all slow rotators ($\lessapprox 100$ km s$^{-1}$) except for three fast-rotating Class III objects. Additionally, in the same sample of 118, 37 are X-ray sources, and 22 having available $v \sin i$ data show a systematically slower rotation than X-ray quiet sources. Our findings suggest that, while young
stellar disks in intermediate-mass
stars contribute to early
spin-down, high-energy processes traced by X-ray emission during this phase could be an additional channel for angular-momentum loss in these
stars.
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All authors Khushboo K. Rao, Wen-Ping Chen, Hsiang-Yu Chen, Kristen Dage, Stella S. R. Offner
Soft Condensed Matter
A Phase-Field Study of Desiccation Crack Pattern Maturation under Drying-Wetting Cycles
Hiroki Fukushima and Satoshi Yukawa
The characteristic intersection angle of the desiccation crack relaxes from near \ang{90} toward \ang{120} under repeated drying–wetting cycles. However, the theoretical understanding of this relaxation is insufficient, especially the modeling of the drying–wetting cycles. Here we introduce a phase-field model of desiccation fracture, extending the model proposed in previous studies by adding crack healing and a scar effect left by past cracks. By repeating drying–wetting cycles in a finite element simulation, we find that the angle distribution develops a growing peak near \ang{120} as the cycle number increases, consistent with experiments. The standard deviation of the intersection angle from \ang{120} relaxes exponentially with a characteristic time of about 2.85 cycles. These results are consistent with experiments, except that the characteristic time is slightly smaller than the experimental value. Crack energy dominates the total energy and also relaxes exponentially with nearly the same characteristic cycle as the angle relaxation. This decay is driven mainly by a shortening of the effective crack length rather than a change in effective fracture toughness.
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Quantum Gases
Transdimensional quantum droplets in an optically trapped Bose mixture
Xiaoran Ye, Yi Zhang, Ziheng Zhou et al. (+1 more)
We study
quantum droplets in a symmetric two-component Bose mixture with interspecies $p$-wave interactions and a two-dimensional transverse optical
lattice. The
lattice drives a crossover from an anisotropic three-dimensional gas to weakly coupled one-dimensional tubes. We calculate the ground-state energy and
quantum depletion at the Gaussian level and derive their limiting forms. At $y=g_{12}/g=-0.95$, where the bare mean field is repulsive and no free-space droplet exists, the calculated bulk equation of state supports a self-bound minimum across the crossover: a negative
lattice contribution at order $n^{2}$ supplies the attraction in the three-dimensional regime, and attractive fluctuations do so in the quasi-one-dimensional regime, with the intermediate, transdimensional range described quantitatively by neither limit. The interspecies $p$-wave interaction modifies only the
spin branch. In the parameter range studied, increasing its strength lowers the
equilibrium density across the crossover, consistently with a weakening of the induced binding.
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All authors Xiaoran Ye, Yi Zhang, Ziheng Zhou, Zhaoxin Liang
Statistical Mechanics · Cross-listed from math.PR
Recurrence and transience of random walks with drift $\rho x^{\alpha}/t^{\beta}$
Ngo P. N. Ngoc and Tuan-Minh Nguyen
Menshikov and Volkov [Electron. J. Probab. 13 (2008)] studied recurrence and transience of a class of Markovian random walks on $\mathbb R_+$ whose conditional drift depends on both time and position and is of order $\rho x^\alpha t^{-\beta}$ with $\rho>0$. The case on the critical line $2\beta-\alpha=1$, with $\alpha\in(-1,1)\setminus\{0\}$, remained open. We prove recurrence in this remaining case. Furthermore, we establish recurrence and transience criteria that complete the classification for $-1<\alpha<1$ and $\beta\ge 0$, without assuming the Markov property and under weaker assumptions on the increments than those imposed by Menshikov and Volkov.
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Soft Condensed Matter
Slow Dynamics and the Geometry of Jammed Packings
Eddie Bautista and Eric Corwin
Saddle points in the energy landscape of granular packings dominate the discrete steepest descent dynamics and ultimately determine the path that an out of mechanical
equilibrium packing will follow and the resulting stable minimum that it will find. The saddle points that ultimately determine the resulting minima tend to be low-index saddle points. For models with an analytic energy landscape, such as the $p$-
spin model, the steepest descent minimization path is affected by higher-index saddle points, which pull the system towards saddle points of decreasing index before arriving at the minima. Here, we examine the steepest descent minimization path of granular packings and compare them to the $p$-
spin model. We show that the granular packing steepest descent minimization paths act like their smooth energy landscape counterparts and get attracted by saddle points. The index versus time curves for all models follow a shifted, stretched exponential. We further show that the shape parameter for the granular packings is unchanged when the energy landscape is modified to become analytic (Gaussian potential in a harmonic well) or non-local (Mari-Krzakala-Kurchan). The $p$-
spin, on the other hand, has a significantly larger shape parameter. The reason is not due to the dimensionality, packing fraction, nonanalyticity, or the locality of the
Hamiltonian of the models. The exact reason for the discrepancy in the shape parameter is \st{still} an unsolved mystery.
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Quantum Physics
Engineered two-photon dissipative confinement of a Kerr-cat qubit using SISIS quantum circuit refrigerator
Shumpei Masuda, Tsuyoshi Yamamoto, Shuji Nakamura et al. (+2 more)
Kerr-cat
qubits realized in periodically driven superconducting nonlinear resonators are a promising platform for
quantum information processing with biased noise. Pure dephasing in such systems induces leakage out of the
qubit subspace, motivating the use of
quantum circuit refrigeration (QCR) to remove excess excitations. While conventional
superconductor–
insulator–normal-metal–
insulator–
superconductor (SINIS)-based QCRs can suppress leakage via single-
photon absorption, they also enhance QCR-induced phase-flip errors. Here we investigate a QCR based on a
superconductor–
insulator–
superconductor–
insulator–
superconductor (SISIS) junction coupled to a Kerr parametric oscillator (KPO). We show that a SISIS-based QCR can operate in a regime where single-
photon processes are suppressed while two-
photon absorption dominates. As a result, the proposed SISIS-based QCR achieves strong suppression of dephasing-induced leakage while substantially reducing the increase in phase-flip errors associated with QCR operation. These results demonstrate that the proposed SISIS-based QCR provides an effective approach for mitigating leakage while limiting QCR-induced phase-flip errors in Kerr-cat
qubits.
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All authors Shumpei Masuda, Tsuyoshi Yamamoto, Shuji Nakamura, Daichi Sugiyama, Akiyoshi Tomonaga
Solar and Stellar Astrophysics
A prolonged plateau-to-tail transition in the Type II supernova SN2025abyc
Luhan Li, Bo Wang, Jujia Zhang et al. (+6 more)
We present optical photometric and spectroscopic observations of the Type II
supernova SN2025abyc. During the optically thick phase between approximately 10 and 70 d after explosion, its light curves show strongly wavelength-dependent decline rates of approximately 2.7, 2.1, 0.9, and 0.8 mag/100d in the g, c, r, and o bands, respectively. At approximately 70 d, the light curves begin to depart from their nearly linear plateau
evolution and gradually transition toward the radioactive tail. A
Fermi-Dirac fit to the well-sampled ATLAS o-band light curve yields a transition midpoint of t_PT ~ 100.5d. The interval between the end of the linear plateau and this transition midpoint is approximately 30 d, indicating a prolonged plateau-to-tail transition. This timescale is comparable to those measured for SN2013by, SN2013ej, and SN2014G. Spectroscopically, at +13 d post-explosion, the Halpha profile appears weak and broad, whereas Hbeta and Hgamma display clear P-Cygni profiles. This morphology can be explained by the normal early spectroscopic
evolution of SNe II, although partial filling of the Halpha absorption trough by emission associated with circumstellar interaction cannot be excluded. SN2025abyc otherwise follows the general photospheric velocity
evolution of SNe II, while remaining toward the high-velocity side of the comparison distribution in Halpha, Hbeta, and FeII. Exploratory light-curve modelling suggests a synthesized Ni mass of approximately 0.03-0.04
solar mass. We suggest that the extended circumstellar environment, Ni distribution, and hydrogen-envelope structure could all play a role in shaping the observed light-curve
evolution, particularly the prolonged plateau-to-tail transition.
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All authors Luhan Li, Bo Wang, Jujia Zhang, Zhengyang Zhang, Xinjie Luo, Shiyang Dong, Saien Xu, Zhengwei Liu, Zhanwen Han
Lattice Field Theory
Properties of the positive and negative parity charm-strange and bottom-strange mesons $D_s$, $D_s^*$, $D_{s0}^*$, $D_{s1}$, $B_s$, $B_s^*$, $B_{s0}^*$, $B_{s1}$ from lattice QCD: masses, decay constants, and compositeness
Forrest Guyton and Stefan Meinel
We present a
lattice-QCD determination of properties of the lightest scalar, pseudoscalar, vector, and axial-vector heavy-strange
mesons. This includes the decay constants of all
mesons, and the binding energies and Weinberg compositeness parameters of the positive-parity states. The calculations are performed with domain-wall
fermions for the light and strange
quarks and anisotropic clover actions for the charm and bottom
quarks. We use seven ensembles generated by RBC/UKQCD with pion masses ranging from 431 MeV to 139 MeV and
lattice spacings ranging from 0.114 fm to 0.073 fm, which allows us to perform combined
chiral and continuum extrapolations. For the negative-parity
mesons, we obtain $f_{D_s}=251.4(2.1)(0.4)(2.5)\:{\rm MeV}$, $f_{D_s^*}=272.5(4.3)(1.0)(2.7)\:{\rm MeV}$, $f_{B_s}=228.4(5.8)(0.5)(2.3)\:{\rm MeV}$, $f_{B_s^*}=229.2(4.4)(0.8)(2.3)\:{\rm MeV}$, $f_{D_s^*}/f_{D_s}=1.086(14)(11)$, and $f_{B_s^*}/f_{B_s}=1.003(22)(10)$. In the positive-parity sector, the finite-volume energies and decay constants are extracted using the GEVP from correlation
matrices with three different types of
hadron interpolating operators, including operators with covariant derivatives and
meson-
meson-scattering operators at both source and sink. After extrapolation to the physical point, we obtain $f_{D^*_{s0}}=136.6 (8.0)(4.0)(1.4)$ MeV, $f_{D_{s1}}=200 (33)(24)(2)$ MeV, $f_{B^*_{s0}}=207 (12)(8)(2)$ MeV, and $f_{B_{s1}}= 196 (16)(11)(2)$ MeV. Our results for $f_{B^*_{s0}}$ and $f_{B_{s1}}$ are the first from
lattice QCD. Lüscher's method is used to find the infinite-volume bound-state masses. At the physical point, we obtain $m_{D^*_{s0}}-m_D-m_K=-48 (14)(4)$ MeV, $m_{D_{s1}}-m_{D^*}-m_K=-61 (15)(2)$ MeV, $m_{B^*_{s0}}-m_B-m_K= -69 (13)(4)$ MeV, and $m_{B_{s1}}-m_{B^*}-m_K=-77 (10)(5)$ MeV. Our analysis shows consistency with the positive-parity states being predominantly molecular.
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Mathematical Physics · Cross-listed from math.DS
Admissible Fourier Lengths, KAM Reducibility, and Spectral Applications
Xueyin Wang and Jiangong You
We develop a perturbative KAM reducibility theory for one-frequency $\mathrm{SL}(2,\mathbb{R})$ cocycles based on an admissible
Fourier length $\ell$. The regularity relevant to the iteration is measured by positive adapted
Fourier width rather than ordinary smoothness in the Euclidean length $|n|$. The same length governs
Fourier decay, truncation and resonance scales, and the arithmetic condition controlling the small divisors. This framework contains the classical analytic and Gevrey settings, while non-monotone choices of $\ell$ allow classical nowhere differentiable Weierstrass-type perturbations and continuous perturbations outside every positive Hölder class. As spectral applications, we obtain purely absolutely continuous spectrum for every phase and $1/2$-Hölder continuity of the integrated density of states for the associated quasiperiodic Schrödinger operators. The Aubry dual has pure point spectrum for Lebesgue almost every dual phase, with eigenfunctions exponentially localized in the metric induced by $\ell$. We also construct nowhere differentiable quasiperiodic potentials with purely absolutely continuous Cantor spectrum.
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Quantum Physics
Full-Rank Noise Forbids Long-Range Entanglement Swapping
Xuan Du Trinh, Nicholas Pardave, Angie Huang et al. (+2 more)
Quantum repeaters extend
entanglement by swapping noisy elementary links. We prove that full-rank noise forbids this at long range: for any entangled full-rank two-
qubit link, there is a finite depth beyond which no end-to-end
entanglement can be established regardless of the measurement outcomes on intermediate
qubits, even under any adaptive postselected strategy. This limit is set by one spectral parameter of the link, giving a no-go criterion for repeater routing. In contrast, we construct link state families of rank three and rank two that admit postselected measurement outcome branches of exponentially small probability but with strictly positive concurrence at every finite depth. Swapping experiments on a superconducting processor show that links of equal initial concurrence but different rank behave differently under postselected swapping. In the
language of many-body physics, the chain is a
matrix-product density operator, and full-rank bonds forbid long-range localizable
entanglement, while rank-deficient bonds can sustain it.
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All authors Xuan Du Trinh, Nicholas Pardave, Angie Huang, Xiangyi Meng, Nengkun Yu
Mesoscale and Nanoscale Physics
In-plane magnetic field control of anomalous Hall response enabled by magnetic anisotropy engineering
J. C. Rodriguez E., E. De Biasi, J. I. Facio et al. (+7 more)
Engineering
magnetic anisotropy provides a powerful route to control magnetization orientation and unlock emerging functionalities in opto-spintronic and current-driven devices. Beyond its role in magnetization reversal, the effective anisotropy can strongly influence the magnetotransport response, offering an additional degree of freedom to tune new device functionalities. In this work, we report a magnetotransport study of a ferrimagnetic [Tb/Co]$_{\times 5}$ multilayer grown with a Tb thickness gradient, whose wedge-shaped tilts the uniaxial anisotropy axis slightly away from the film normal. Anomalous
Hall resistivity measurements from 80 K to 300 K reveal a
spin reorientation transition, while the angular dependence of the magnetotransport responses exposes the crucial role of the tilted anisotropy. A simplified macrospin model reproduces the full angular response across the transition and shows that the observed anomalous
Hall effect when the in-plane
magnetic field is applied originates from the tilt of the uniaxial anisotropy axis, which supplies a built-in
symmetry-breaking mechanism, enabling in-plane field control over the out-of-plane anomalous
Hall response, sign included. These findings establish tilted
magnetic anisotropy as a promising route toward
Hall effect-based sensor applications and highlight Tb/Co multilayers as a versatile platform for anisotropy-engineered spintronic devices.
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All authors J. C. Rodriguez E., E. De Biasi, J. I. Facio, D. Salomoni, S. Auffret, R. C. Sousa, I. L. Prejbeanu, A. Bruchhausen, J. Curiale, L. Avilés-Félix
Mesoscale and Nanoscale Physics
Hai Wang, Woye Pei, Ridong Cong et al. (+14 more)
Spin transistors with its both charge and
spin properties tuned via electrostatic gating are believed capable for widespread use, which however have proven challenging due to the extreme rareness of their physical base –
magnetic semiconductors. The latter are limited within very few systems including diluted
magnetic semiconductors (DMS) and two-dimensional
ferromagnetic semiconductors (2D-FMS), and known to suffer from inadequate gate-tunability of their electric and/or
magnetic properties. Here, we show a substrate engineering paradigm by interfacing few-layered Cr$_{2}$Ge$_{2}$Te$_{6}$ (FL-CGT) with an
antiferromagnetic insulator CrOCl. Owing to the subtle interfacial charge transfer couplings, CGT can be drastically turned from an ambipolar
semiconductor into a high performance P-type
semiconductor. When cooled below the Curie temperature, the ON-OFF ratio in such substrate-boosted FMS field-effect transistor (FET) reaches 10$^{5}$ with its coercive field $H_{c}$ of
magnetic hysteresis loop tunable by a factor of more than 200$\%$, enabling {gate-assisted
magnetic switching in the prototype semiconducting
spin transistor architecture}. A crossover from critical power-law scaling to a dual power-law behaviour under heavy hole doping was further observed. Our findings {signify} an efficient interfacial charge transfer and electrically modulated
magnetic anisotropy energy supported by calculations. This high performance P-type FMS-FET system suggests that active substrate-boosting paradigm might be a powerful path for the investigation of future gate-tunable spintronic devices.
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All authors Hai Wang, Woye Pei, Ridong Cong, Xiaoyan Liu, Yuping Tian, Kenji Watanabe, Teng Yang, Takashi Taniguchi, Xiangru Kong, Weijiang Gong, Guowei Zhou, Xiaoxi Li, Hanwen Wang, Jixuan Wu, Jiezhi Chen, Xiaohong Xu, Tongyao Zhang
Mathematical Physics · Cross-listed from math.PR
Spectral properties of Random Matrices
Anastasis Kafetzopoulos
We give the theoretical foundations of random
matrix theory through the definitions of a random
matrix, a random probability measure and the corresponding empirical spectral distribution. The technical tool we use is the Stieltjes transform method through which we prove optimal convergence of the empirical spectral distribution of random sample covariance
matrices to the deterministic Marchenko-Pastur distribution. We also give new results about the
rigidity of the
eigenvalues of this random sample covariance
matrix and the rate of their convergence. We then define the Dyson equation method to prove new local laws about a random
matrix model that interpolates between the Marchenko-Pastur distribution, the elliptical law and the circular law. Through our work these local laws can be considered universal.
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High Energy Physics (Phenomenology)
Axionic Wormholes in Metric-Affine Gravity
Shonosuke Takeshita and Naoki Yoshioka
The
axion is a promising candidate for solving the strong CP problem. To solve this problem, the global U(1)
symmetry must be preserved to a high degree of accuracy. However, it is well known that global
symmetries are explicitly violated by
quantum gravity effects, giving rise to what is referred to as the
axion quality problem. In this paper, we investigate axionic wormholes as a source of explicit U(1) violation in Metric-Affine
Gravity. This framework allows for spacetime torsion and non-metricity, which accommodate additional
curvature-like and topological terms, such as the Holst and Nieh–Yan terms, that are absent from the metric and Palatini formalisms. We show that non-minimal couplings to these terms modify the wormhole dynamics and enhance the Euclidean wormhole action, thereby alleviating the
axion quality problem. We also find that the viable parameter space is enlarged when two of these couplings are simultaneously present. We further identify representative parameter regions where the alleviation of the
axion quality problem is compatible with inflationary constraints.
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Quantum Physics
On-chip squeezed light in the audio frequency band
Xuezhi Zhu, Yunyun Cao, Rui Liu et al. (+7 more)
Squeezed light in the audio-frequency band is a key resource for
quantum metrology and
quantum sensing. However, realizing stable audio-frequency squeezed light on integrated photonic platforms remains challenging due to technical noise and the difficulty of scalable phase referencing. Here, we demonstrate on-chip generation of audio-band two-mode squeezed states down to 60 Hz in a silica microcavity. To enable phase-stable operation without directly locking fragile
quantum modes, we develop a coherent-comb control method in which a weak electro-optic reference comb co-propagates with the
vacuum at the
quantum frequency modes in an orthogonal polarization. This scheme provides quadrature measurement and long-timescale phase stability, thereby enabling covariance-
matrix reconstruction. We verify the
entanglement with the positive partial transposition criterion, which confirms inseparability via a minimum
symplectic eigenvalue of 0.395 ($<0.5$). Our results establish an experimentally accessible route toward on-chip phase-stable audio-band squeezing and support the scalable framework for continuous-variable
quantum information processing with integrated photonics.
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All authors Xuezhi Zhu, Yunyun Cao, Rui Liu, Yaya He, Fan Zhang, Yaqing Zhang, Shiwei Du, Meihong Wang, Xiaoshun Jiang, Xiaolong Su
Applied Physics
Janus Dipoles: Fundamentals, Realizations, and Emerging Applications
Bo Xue, Qiuyang Li, Yuqiong Cheng et al. (+10 more)
The Janus dipole - featuring orthogonally oriented electric and
magnetic dipoles with a 90-degree phase difference - has emerged as a powerful paradigm for wave manipulation. Unlike traditional Huygens dipoles used for directional control, this unique configuration exhibits strongly asymmetric, face-selective near-field behavior while maintaining a quasi-isotropic far-field radiation pattern. These remarkable properties make the Janus dipole an essential platform for directional wave shaping, with wide-ranging applications in on-chip photonics,
quantum interactions, and wireless power transfer. This review systematically traces the rapid development of the Janus dipole from its foundational theoretical inception to its diverse implementation platforms across optical, microwave, and acoustic frequencies. In this paper, we explore the governing principles, classify realization strategies into passive Janus dipoles, active Janus dipoles, and advanced near-field coupling control, and highlight emerging frontiers. By bridging foundational electrodynamics with advanced device engineering, this paper serves as an essential reference and roadmap for researchers designing next-generation, highly integrated, and compact wave-manipulation systems.
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All authors Bo Xue, Qiuyang Li, Yuqiong Cheng, Wenbo Ma, Xuhuinan Chen, Wanting Tong, Junho Jung, Runqi Jia, Ke Chen, Yijun Feng, Xiao Lin, Shubo Wang, Alex M. H. Wong
Solar and Stellar Astrophysics
Science operation, data handling, and ground support system of the SOLAR-C mission
Shin Toriumi, Mari Nishiyama, Keiichi Matsuzaki et al. (+16 more)
SOLAR-C is an international
solar-observing satellite mission led by Japan Aerospace Exploration Agency (JAXA). It aims to elucidate mass and energy transport in
solar atmospheres through extreme ultraviolet (EUV) spectroscopy. The mission carries the EUV High-throughput Spectroscopic
Telescope (EUVST) and the
Solar Spectral Irradiance Monitor (SoSpIM), enabling comprehensive observations across a wide temperature range (10^4 K to 10^7 K) with minimum temperature gaps and high spatial and temporal resolution. To achieve its science objectives regarding atmospheric heating and
solar flare eruptions,
SOLAR-C implements a flexible and responsive operational procedure and a data processing system, while building on the heritage of the Hinode and IRIS satellites. The Chief Observer creates observation timelines that include core observation plans and approved proposed plans while taking into account the
solar activity levels. A SpaceWire communication architecture is employed onboard the spacecraft, and a method is implemented in which the mission instrument temporarily acts as the network master during data transfer to support the high data rate requirements. Telemetry is downlinked at ground stations worldwide and gathered at the Institute of Space and Astronautical Science, JAXA. The EUVST data are calibrated at the
SOLAR-C Science Center at Nagoya University, while the SoSpIM data are calibrated at the Processing and Archiving Facility before being integrated into the science data products. The data will be made publicly available immediately. The integrated operational scheme for this mission is expected to advance our understanding of
solar atmospheric heating and
flare processes.
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All authors Shin Toriumi, Mari Nishiyama, Keiichi Matsuzaki, Toshifumi Shimizu, Hideki Kato, Jun Matsumoto, Mizuho Uchiyama, Kota Miyoshi, Daiki Yamasaki, Hirohisa Hara, Yukio Katsukawa, Masahito Kubo, Ryohko Ishikawa, Takenori J. Okamoto, Shinsuke Imada, Satoshi Masuda, Kyoko Watanabe, Yusuke Iida, Ayumi Asai
Materials Science
U-Shaped Fermi-Level Dependence of Point-Defect Aggregation Enthalpy in Silicon
Yin Wu, Xiao Kong and Pai Li
Point defects govern the electronic and structural behavior of silicon, yet their configuration and energy depend on both the charge state and the
Fermi level (EF). Using an unbiased global structure search with first-principles calculations, we screened more than 1,500 candidate structures, covering intrinsic defects and C, H, O, N, P, and B
impurities in charge states from -2 to +2. The reaction enthalpy of defect aggregation depends on EF in a U shape, being strongest where the net charge transferred during the reaction vanishes and weaker toward both band edges. This U arises because complexes are more charge-neutral than their isolated constituents, so the net charge transfer changes sign across the gap. The point where this sign change occurs is set by the transition levels of the specific defects. For typical reactions, the driving force is tunable by 0.3-0.5 eV, which shifts the
equilibrium complex concentration by five to eight orders of magnitude at room temperature. Our results make the
Fermi level a practical lever for defect engineering in as-grown and irradiated silicon.
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Cosmology and Nongalactic Astrophysics
Two-parameter continuous deformation of Starobinsky inflation as a bridge between Planck and ACT DESI data with $N_\star\in(50,60)$
G. German
We present a family of plateau-type inflationary potentials, eq.~\eqref{Vgeneral}, and analyze a two-parameter $\alpha\beta$-Starobinsky specialization that interpolates continuously between a maximal plateau ($V\!\to\!V_0$) and a submaximal plateau ($V\!\to\!V_\infty<V_0$), where $V_0$ is the overall scale of the potential. In the $\beta\!\to\!0$ limit our framework reproduces the $\alpha$-Starobinsky predictions $n_s\simeq 1-2/N_\star$ and $r\simeq 12\alpha/N_\star^2$. For $\beta>0$ with $x_\star\gg 1/\beta$ the slow-roll scaling laws change to $n_s\simeq 1-\frac{4}{3N_\star},\, r\simeq\mathcal{C}(\alpha,\beta)\,N_\star^{-4/3},$ with an explicit coefficient $\mathcal{C}(\alpha,\beta)$ set by the plateau truncation. This deformation lifts $n_s$ at fixed $N_\star$ while further suppressing $r$, reconciling the Planck~2018 constraint $n_s=0.9649\pm0.0042$ (68% CL) and BICEP/Keck18 data $r_{0.05}<0.036$ (95% CL), with the higher central values $n_s\sim0.97$–$0.98$ preferred by ACT+DESI~DR2 (BAO), within the theoretically motivated interval $N_\star\in(50,60)$ and without exotic reheating. We provide an exact identity for $V/V'$ enabling analytic control of $N_\star$, a practical crossover criterion $\beta\,x_\star\ll1$ vs.\ $\gg1$, and a transparent mapping between $(\alpha,\beta)$ and the observables $(n_s,r,N_\star)$. These yield sharp, testable signatures, particularly the softened $N_\star$-scaling of $r$, that distinguish a maximal from a submaximal plateau with upcoming CMB and LSS data.
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Solar and Stellar Astrophysics
Classical Nova V1405 Cas Had $M_{\rm ejecta}$$>$$M_{\rm accreted}$ and so is Unlikely to be a Type Ia Supernova Progenitor
Bradley E. Schaefer
Nova 2021 Cassiopeia (V1405 Cas) was an ordinary J(175) neon nova with the white
dwarf mass estimated to be $M_{\rm WD}$=0.60$\pm$0.10 $M_{\odot}$. I found an orbital period of $P$=0.1884 days, and have tracked 20 times of photometric minima from 2013–2025. I measure that $P$ increased from before to after the eruption with $P_{\rm pre}$=0.1883919$\pm$0.0000018 days and $P_{\rm post}$=0.1884043$\pm$0.0000018 days, for $\Delta P$/$P$=66$_{-18}^{+21}$ parts-per-million. With correction for the angular momentum loss by the binary during the eruption, I derive that the nova ejected $M_{\rm ejecta}$=7.5$\times$10$^{-4}$ $M_{\odot}$, with an extreme range of (2.9–40)$\times$10$^{-4}$ $M_{\odot}$. The mass accreted during the previous eruption cycle comes from the trigger mass, and is $M_{\rm accreted}$=(1.6$\pm$0.4)$\times$10$^{-4}$ $M_{\odot}$. V1405 Cas provides counterexamples against five claims about CV
evolution that have dominated since the 1980s. First, V1405 Cas has positive $\dot{P}$, and this is contrary to the
Magnetic Braking Model. Second, the $\Delta P$ is 20$\times$ too small to allow the system to fade into a hibernation state. Third, $M_{\rm WD}$ is decreasing over time, as shown by $M_{\rm ejecta}$$>$$M_{\rm accreted}$ and by being a neon nova. Fourth, V1405 Cas is not a Type Ia
supernova progenitor, for the same reasons. Fifth, the orbital period of V1405 Cas increased by $+$75 ppm from 2013–2025, as a counterexample to the pervasive idea that cataclysmic variables are universally declining in period from
evolution. V1405 Cas is the latest of recent measures of $\Delta P$ and $\dot{P}$ for 52 cataclysmic variables and 25 X-ray binaries that have together refuted all five claims.
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