Quantum Physics
A robust digital receiver architecture for continuous-variable quantum key distribution
Lu Fan, Xuesong Xu, Miao Yu et al. (+6 more)
Continuous-variable
quantum key distribution utilizes advanced digital signal processing techniques to mitigate channel impairments, driving the progress of high-performance
quantum secure communications. Specifically, digital heterodyne receivers are commonly implemented using down-conversion
algorithms to detect both components simultaneously where the signal is modulated onto an intermediate frequency to avoid low-frequency noise and bypass stringent optical phase-locking requirements. However, a rigorous analysis of the
quantum security implications of the digital down-conversion
algorithm remains absent. In this paper, we investigate the
algorithm process from the perspective of
quantum operator
evolution, revealing that the frequency folding effect inherent in down-conversion inevitably mixes the image-frequency information into the baseband signal. To address this issue, we propose a novel operator reconstruction detection scheme based on dual-path digital heterodyne receiver. By performing a non-equal weighted combination of the output operators along two optical paths in the digital domain, this scheme perfectly cancels out the image-frequency operator physically. The robust receiver architecture preserves the baseband noise-suppression advantages, inherently achieves perfect mode balancing for asymmetric optical detection losses, and fundamentally closes the image-frequency crosstalk. Practical experiments have validated the feasibility of the proposed architecture and its effective suppression of image-frequency noise, achieving a performance of 11.4 Mbps @ 42 km. This work lays a solid theoretical and algorithmic foundation for future high-performance, highly secure digital continuous-variable
quantum key distribution systems.
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All authors Lu Fan, Xuesong Xu, Miao Yu, Zhengyu Li, Yunsong Yin, Hao Shi, Xuanyu Guo, Song Yu, Yichen Zhang
Materials Science
Evolution and breakdown of chiral anomaly in Weyl semiconductor tellurium
Zhifeng Xue, Jiaji Zhao, Yi Ji et al. (+16 more)
Chiral anomaly in topological materials manifests as negative longitudinal magnetoresistance, yet the tunability and
evolution of this effect remain elusive. Here we show that doped tellurium serves as a versatile platform to realize a giant negative longitudinal magnetoresistance that is highly tunable via the Fermi level and
magnetic field. By moving the Fermi level towards the Weyl point, we observe a pronounced enhancement of negative magnetoresistance, which arises from chiral anomaly and robustly persists up to ambient temperature. Beyond the
quantum limit, the system exhibits positive linear magnetoconductance, serving as a compelling transport signature of the chiral anomaly in the lowest Landau level. Notably, in the extreme
quantum limit at cryogenic temperatures, the magnetoresistance undergoes a dramatic reversal from negative to positive. This reversal points to a potential field-induced phase transition into a collective electronic state driven by enhanced electron-electron interactions. Our findings provide valuable insights into the unconventional chiral transport and emergent correlated
quantum states under extreme
magnetic fields.
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All authors Zhifeng Xue, Jiaji Zhao, Yi Ji, Fuyang Chen, Nannan Tang, Gangjian Jin, Bing Shen, Bin Wang, Yang Wang, Mingxi Chi, Jin-Zhu Zhao, Ruiqiang Wang, Qizhong Zhu, He Wang, Huakun Zuo, Donghui Guo, Dingyong Zhong, Mingxun Deng, Huichao Wang
Quantum Physics
All-optical deconvolution via quantum cross-correlation spectroscopy with bright twin beams
Yujiro Eto
The resolution of spectroscopic measurements is fundamentally limited by the convolution between a system's intrinsic response and the instrument response function, creating an ill-posed inverse problem. While entangled
photons can theoretically bypass these limits, low
photon flux has hindered their experimental realization. Here, we propose
quantum cross-correlation spectroscopy (QCCS), utilizing macroscopic twin beams (signal and idler beams) to physically circumvent this convolution limit in coherent anti-Stokes Raman scattering. Employing the signal beam as a broadband probe, QCCS achieves all-optical deconvolution through a correlation-enhanced sum-frequency generation channel between the convoluted anti-Stokes and idler beams. By subtracting the uncorrelated background using a 500-femtosecond temporal window, we successfully retrieve narrow Raman bands (8 cm^{-1} and 15 cm^{-1}) completely obscured by a 75 cm^{-1} probe bandwidth without numerical deconvolution or prior knowledge. Our results establish macroscopic
quantum correlations as a robust resource for high-fidelity spectroscopy, paving the way for ultrashort-pulse-free operando studies under natural, incoherent excitation conditions.
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Astrophysics of Galaxies
A Relationship Between Fast Radio Burst Dispersion Measure and Host Galaxy Inclination
Lachlan Marnoch, Stuart D. Ryder, Sunil Simha et al. (+9 more)
It is commonly thought that fast
radio bursts (FRBs) trace
star formation, and that they are produced by magnetars. Both hypotheses imply that their sources are hosted primarily (but not exclusively) in galactic disks. Although there is evidence in that direction, it has yet to be shown conclusively. In addition, a tension exists with the fact that at least one FRB source is found in a globular cluster far from the disk of the host. If FRBs originate primarily in disks, the
galaxy orientation could leave an impression in the sample of observed FRBs, either as a selection bias against FRBs in edge-on
galaxies or as a correlation with DMHost. Statistical tests against the inclinations of FRB host
galaxies, derived from parametric morphology applied to optical and near-infrared imaging, can search for these effects. Such a search requires an adequately large sample of known FRB hosts that have been imaged to a sufficient depth, while estimates of DMHost also require the
redshift of each host to be known. These conditions are best met in the Commensal Real-time ASKAP Fast Transient (CRAFT) survey sample of FRB host
galaxies, for which the majority have been imaged at optical wavelengths with FORS2 on the Very Large
Telescope (VLT). Here these data are fitted with the morphology software GALFIT to derive the elliptical axis ratio q (a proxy for inclination) for 34 hosts from the CRAFT sample, detected with ASKAP and followed up with VLT imaging. We find no bias against FRB detections from edge-on
galaxies; instead, we uncover a new relationship between the inclination of an FRB host
galaxy and DMHost. This is consistent with a primarily disk-based origin for CRAFT FRBs. Using this relationship we are able to reduce the scatter of the host sample about the Macquart relation by 40%, demonstrating a new empirical method for estimating DMHost that requires only deep optical imaging.
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All authors Lachlan Marnoch, Stuart D. Ryder, Sunil Simha, Alexa C. Gordon, R. M. Shannon, Nicolas Tejos, Marcin Glowacki, Ziteng Wang, Elizabeth K. Mahony, J. Xavier Prochaska, Wen-fai Fong, Richard M. McDermid
Nuclear Theory
Octupole correlations in the excited $0^+$ states and two-neutron transfers in actinide nuclei
Kosuke Nomura
Impacts of octupole correlations on low-energy excited $0^+$ states and two-
neutron transfer intensities in Ra and Th isotopes are analyzed within the interacting
boson model, using the
Hamiltonian parameters that are obtained from microscopic nuclear density functional theory calculations. Incorporating the octupole degree of freedom in the model is shown to give an overall reasonable description of the ground-state-band energy levels and to lower the $0^+_2$ ones significantly. The calculation yields a number of excited $0^+$ states, most of which are formed by the configurations of more than one octupole
boson. Octupole correlations make significant contributions to the $0^+_1 \to 0^+_2$ $(p,t)$ and $(t,p)$ transfer intensities in those
nuclei in which the octupole collectivity is most enhanced. Behaviors of the predicted transfer intensities with the increasing
neutron number along the isotopic chain reflect nuclear structural
evolution.
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High Energy Physics (Phenomenology)
Dijet hadrochemistry: tomography of jet-induced medium excitation and diffusion wake
Cong Yi, Xiang-Yu Wu, Zhong Yang et al. (+4 more)
Energetic partons traversing the
quark-gluon
plasma in relativistic heavy-ion collisions induce a medium response that modifies the production of associated
hadrons, whose chemical composition provides a sensitive probe of this response. We study jet-associated hadrochemistry using the coupled linear Boltzmann transport and hydrodynamics model with a hybrid hadronization scheme that combines Cooper–Frye particlization,
quark coalescence and string fragmentation. For inclusive charged jets in $p+p$ and 0–10% central Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$~TeV, the calculated in-cone $K/\pi$ and $p/\pi$ ratios are enhanced in Pb+Pb relative to $p+p$ collisions, consistent with preliminary ALICE measurements, with coalescence between shower and thermal partons providing a substantial contribution. Extending the analysis to dijet events, we predict that both ratios are enhanced around the leading and subleading jets, more strongly around the subleading jet and more pronounced for larger radial size. After mixed-event acceptance correction and sideband background subtraction, the yields of associated pions, kaons and
protons all become negative near $|\Delta\phi|\simeq\pi/2$, signaling a depletion caused by the
diffusion wake. The $K/\pi$ and $p/\pi$ ratios of these deficits remain finite and exceed the $p+p$ values around the jet peaks, indicating that the missing
hadrons originate from jet-excited medium. These results establish dijet hadrochemistry as an experimentally accessible tomographic probe of jet-induced medium excitation and the
diffusion wake.
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All authors Cong Yi, Xiang-Yu Wu, Zhong Yang, Pi Duan, Guang-You Qin, Xin-Nian Wang, Wenbin Zhao
Astrophysics of Galaxies
Redshifted Cool Gas in the Disturbed HI Disk of the Starburst Dwarf NGC 4214
Shulan Yan, Taotao Fang, Xiaochuan Jiang et al. (+4 more)
We report redshifted cool gas toward the central
star-forming region of the nearby starburst dwarf
galaxy NGC 4214. HST/COS spectra show low-ionization absorbers redshifted relative to the systemic velocity, most clearly in SII ($\Delta v=19.8\pm2.6\ {\rm km\,s^{-1}}$) and supported by MgII ($\Delta v=30.3\pm3.0\ {\rm km\,s^{-1}}$), while PII remains tentative ($\Delta v=7.5\pm3.4\ {\rm km\,s^{-1}}$). The Keck/HIRES spectra also reveal a redshifted CaII absorption component ($\Delta v=25.6\pm1.5\ {\rm km\,s^{-1}}$). Because the absorption is detected against the central UV or optical continuum, the gas must lie in the foreground of the
star-forming region and is moving away from the observer and toward the background UV source in projection. A VLA–THINGS HI spectrum extracted at the COS position within one VLA beam also shows a redshifted neutral component at $v_{\rm hel}=329.2\pm0.9\ {\rm km\ s^{-1}}$, offset by $38.2\pm1.3\ {\rm km\ s^{-1}}$ from systemic and by $27.6\pm1.0\ {\rm km\ s^{-1}}$ from the dominant local HI component. The FAST HI mapping further reveals an extended, kinematically disturbed neutral disk, with residual structures relative to a warped-disk model. Together, the redshifted UV absorption, the redshifted HI component, and the disturbed large-scale HI velocity field show that the central anomalous cool gas is observed in a
galaxy with a disturbed extended neutral disk. This geometry suggests that the redshifted cool gas may trace inflow or recycled fallback toward the central region, although warped-disk or non-circular disk motions cannot be fully excluded.
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All authors Shulan Yan, Taotao Fang, Xiaochuan Jiang, Junfeng Wang, Qingzheng Yu, Chuanpeng Zhang, Ming Zhu
Quantum Physics
Error Mitigation by Zero-Noise Extrapolation (ZNE) in Indirect-Control System
Arijit Das and Masaki Owari
The indirect-control paradigm offers a scalable approach to
quantum computation by restricting external operations to a small subset of
qubits, whereas the entire system evolves under its intrinsic many-body
Hamiltonian. This framework reduces hardware complexity and limits the noise introduced through control channels. Recently, Anan et al. proposed an implementation of the variational
quantum eigensolver (VQE) within this indirect-control architecture. However, the impact and integration of
quantum error mitigation techniques in such a setting remain largely unexplored. In particular, zero-noise extrapolation (ZNE), a widely used error mitigation strategy, has not yet been systematically adapted to indirect-control VQE. A key requirement of ZNE is the controlled amplification of noise, which is commonly achieved through
circuit-level techniques such as
unitary folding. In the indirect-control framework, however,
quantum operations are largely governed by continuous time-
evolution under the system
Hamiltonian, making the construction of physically realizable inverse operations non-trivial. In this study, we investigate the feasibility of implementing ZNE within the indirect-controlVQEframework.We address the challenges associated with
unitary folding in the presence of time-
evolution operators and, with a minimal relaxation of the indirect-control constraint, we propose a ZNE-based error-mitigation strategy that exploits the
symmetry of the one-dimensional XY
spin chain.
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Quantum Physics
Quantum-Circuit Residuals for Receptor Functional Potency Prediction: Predictive Gains and Quadratic Structure
Chenyan Jia, Yaping Ma, Yuen Wang et al. (+1 more)
The predictive performance of neural networks for receptor functional potency modeling depends on both molecular representations and prediction-head design. Using GLP-1R cAMP-related pEC50 prediction as the primary task, we jointly train a classical molecular encoder with a linear base head and a shallow
quantum-
circuit residual head that share the learned molecular representation. We evaluate the models using random and structure-group splits, include tuned Chemprop as a domain reference, and extend the evaluation to ADRB2 and MC4R. Under the GLP-1R structure-group split, the
quantum-residual models reduce mean absolute error relative to the corresponding base models from 0.677 to 0.639 with a multilayer perceptron (MLP) encoder and from 0.680 to 0.641 with a graph neural network (GNN) encoder. In structural control experiments, a parameter-count-matched real-orthogonal control achieves similar predictive performance, suggesting that some
quantum-residual gains may be associated with structured quadratic feature interactions. By combining receptor functional potency prediction with structural analysis of the
quantum residual, this study provides empirical evidence to inform compact residual-head design and highlights the potential of
quantum-
circuit parameterizations for this task.
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All authors Chenyan Jia, Yaping Ma, Yuen Wang, Cong Guo
Quantum Physics
When irrelevance governs: dissipation-regression scaling in open quantum criticality
Fan Zhong
The real-time dynamics of
quantum phase transitions in open systems coupled to finite-temperature environments sits at the heart of contemporary condensed-matter and
quantum-information science. Here, invoking a Schwinger-Keldysh formalism, we uncover that, within the coherence-dominated regime of critical real-time
evolution, a dissipative coupling deemed naively irrelevant determines, counterintuitively, the longest timescale that holds sway. Possessing a well-defined temporal scaling dimension, it engenders a novel dissipation-regression scaling that systematically reproduces the unusual Kibble-Zurek scaling and relaxation observed in recent numerical studies. By contrast, dissipation-dominated dynamics behaves qualitatively differently. There, furthermore, we show that the discretized and diagonalized formulations of the same open
quantum Ising chain realize distinct universality classes.
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Computational Physics · Cross-listed from cs.LG
Low-Rank Kolmogorov-Arnold Generator Flows for Interpretable Operator Learning
Minjong Cheon
Neural operators that learn physical laws from data should generalize beyond their training distribution and expose the learned law in closed form. The Kolmogorov-Arnold neural operator achieves both for position-dependent dynamics by learning a dense pseudo-differential symbol over all positions and frequencies, at a cost that grows with the square of the resolution and with closed forms that must be read out by hand. This dense symbol is unnecessary: a finite-order variable-coefficient differential operator has a symbol whose separation rank is bounded by the number of its coefficient functions, independently of the resolution, and the symbols that this network learns on its own
benchmarks have rank two. We introduce the Kolmogorov-Arnold flow (KAFlow), which learns the generator of a physical operator as a low-rank symbol built from univariate Kolmogorov-Arnold functions, fixes the gauge of these functions so that every term has a unique place, integrates the dynamics with exact exponential integrators, and distills its closed form automatically. On the synthetic
benchmarks of the Kolmogorov-Arnold neural operator, KAFlow lowers the out-of-distribution loss by 3.4 to 11 times and recovers every coefficient to within 10^-4 without symbolic templates, reaching the precision floor of the data. On long-horizon
quantum dynamics, it lowers the state infidelity by up to 6 orders of magnitude, and by 30 times when trained only on position and momentum measurements. KAFlow also learns a variable-order fractional operator 15 times more accurately than existing operator networks and discovers nonlocal, fractional and non-
polynomial dispersion relations on which sparse regression fails.
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General Relativity and Quantum Cosmology
Nephtalí Eliceo Martínez Pérez and Cupatitzio Ramírez Romero
Geometric Inflation adds an infinite tower of
curvature invariants to the Einstein-
Hilbert action while preserving certain key features such as leading to second order modified Friedmann equations for FRW backgrounds. Sourcing them with a perfect barotropic fluid can easily produce a slow-roll inflationary regime, no inflaton field is required. In this work, we perform the Wheeler-DeWitt quantization of minisuperspace
Geometric Inflation models. First, we construct an effective 1D FRW action and perform the
Hamiltonian formulation using both Ostrogradsky's approach and Dirac's
algorithm for constrained systems. The Lagrangian and
Hamiltonian treatment of the perfect fluid is based on Schutz's formalism. Second, we postulate the Wheeler-DeWitt equation and investigate its solutions both analytically and numerically. For radiation we are led to a system of fractional differential equations for which we use Caputo fractional derivative operator. We construct wave packets in momentum space, with the fluid's variable acting as external time parameter.
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Mesoscale and Nanoscale Physics
Parity-Anomalous Hall Response of Chiral Lifshitz Fermions
Yanmiao Han, Rundong Zhao and Yu-Hao Wan
The parity anomaly of a single massless Dirac
fermion is manifested as a half-quantized Hall response once the required parity-breaking regularization is supplied. We study the corresponding response for two-dimensional chiral Lifshitz
fermions. For a node with low-energy coupling (qx +iqy)^N, the Fermi-loop winding number W = N gives an anomalous Hall response {\sigma}xy^anom = (W/2)e^2/h. We examine this mechanism in chiral multilayer Haldane models tuned to a valley-selective critical line, where a single gapless chiral Lifshitz
fermion remains at the K valley. For the AB, ABC, and ABCA stacks, the projected pseudospin textures give W = 2, 3, 4, while Kubo calculations yield {\sigma}xy = (1, 3/2, 2)e^2/h; integrated
equilibrium boundary currents reproduce the same W/2 sequence. Six-terminal simulations with dephasing further show that the Hall conductivity is quantized at W/2 while the longitudinal conductivity remains finite. These results identify gapless chiral Lifshitz
fermions as a higher-order, winding-controlled generalization of the parity-anomalous Hall response, distinct from a
quantum anomalous Hall insulating state even when W/2 is an integer.
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High Energy Physics (Theory)
Distinguishing Flat and Warped Extra Dimensions with Unruh-DeWitt Detectors
Ashmita Das, Anjana Krishnan and Soumitra Sengupta
We examine the response of a two level Unruh-DeWitt (UD) detector interacting with the Kaluza-Klein (KK) mass modes of a bulk scalar field in extra dimensional models. Considering two of the promising extra dimensional models with distinct compactifications, such as large, flat extra dimensions in the Arkani Hamed, Dimopoulos & Dvali (ADD) framework and warped extra dimensions in the Randall-Sundrum (RS) scenario, we compute the profile function of the detector. We extend this computation to the 6 dimensional doubly compactified spacetime geometry. The profile function of the detector has been examined as a function of the energy gap of the detector, the compactification radius of the extra dimension, and the dimensionality of spacetime, requiring the chosen parameter space appropriately such that the gauge hierarchy problem is duly addressed. We find that the pattern of the profile function is dictated by the spacing of the KK mass spectrum and the resolution of the detector. For ADD model, the spacing between successive KK modes decreases with the increasing compactification radius, yielding a smoothly increasing continuum pattern in the profile function. Whereas for the RS warped geometry model, a tiny deviation in the radius of the extra dimension produces a large change in the same, resulting a sharp increment. The resolvability of the KK mode structure is sensitive to the underlying geometry of the spacetime, providing a qualitative distinction between flat and warped extra dimensional scenarios within the UD detector framework.
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High Energy Astrophysical Phenomena
ASKAP Monitoring of the Rubin Deep Drilling Fields
Dougal Dobie, James Freeburn, Iris de Ruiter et al. (+5 more)
In the past decade, time domain astronomy surveys across the multi-messenger spectrum have developed "alert streams" which circulate observational information in real-time to the wider astronomical community. Despite this being standard practice for optical, gamma-ray and gravitational wave time domain astronomy for several years now, this kind of infrastructure has not yet been deployed at-scale for
radio telescopes. We are conducting a long-term monitoring program that targets the Rubin Deep Drilling Fields using the Australian SKA Pathfinder (ASKAP). The primary goal of this program is to provide serendipitous
radio observations of all objects of interest in these fields, and circulate that information in as close to real-time as possible. In this manuscript we outline the survey plans and status, the infrastructure we have developed to disseminate this information and an initial data release comprising 5 months of ASKAP observations of each field (although only 3 months overlaps with Rubin) conducted on an approximately 10 day cadence with a noise level of $\sim 60\,\mu$Jy. As part of this data release, we present updated high-cadence
radio light curves to the tidal disruption event AT2018hyz and the
supernova SN2024abfo along with the discovery of two new
radio variables, a possible tidal disruption event ASKAP J095711.5+051205 and an in-progress extreme scattering event ASKAP J005026.4-422958. The scientific results from this program along with the infrastructure developed to acquire them will lay the foundation for the integration of future
radio imaging surveys into the broader multi-messenger alert stream, leading the way for major facilities such as the Schmidt Observatory System and the SKA.
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All authors Dougal Dobie, James Freeburn, Iris de Ruiter, Katie Auchettl, James Coulson, Brent Miszalski, Anais Möller, Nikhil Sarin
Strongly Correlated Electrons
Odd-Parity Crystalline Electric Field and Multipoles in Icosahedral Quasicrystal and Approximant: Magnetic Toroidal and Electric Dipoles in Ce-Based Systems
Shinji Watanabe, Syunta Furuya and Mitsuaki Kawamura
Quasicrystals (QCs) lack periodic arrangement of atoms but possess unique structural order distinct from periodic
crystals and random systems. The electronic property is far from complete understanding. Here we have formulated not only even-parity but also odd-parity crystalline electric field (CEF) in the Ce-based icosahedral QC and approximant
crystal (AC) on the basis of the point charge model. Under the odd-parity CEF due to local-inversion
symmetry breaking at the Ce site, the hybrid wavefunction of 4f and 5d states at Ce is shown to give rise to the odd-parity multipoles such as electric dipole and
magnetic toroidal (MT) dipole. We have found that the
vortex order in the 1/1 AC where the
magnetic moments on each icosahedron swirl is characterized by the cluster-type MT moment. The ferroic
alignment of the cluster MT moments in the
vortex order gives rise to the electro-
magnetic effect. The cluster-MT moment is shown to be resonated with the MT dipole moments in each icosahedron by tuning the 4f energy level and 5d energy level so as to approach. We have revealed a noncollinear
magnetic structure is stabilized in the ground state of the icosahedral QC cluster, behind which there exists underlying mechanism to prefer the ferroic interaction for the net MT dipole moments between the icosahedrons. We point out that the 4f and 5d energy levels can be made approach at the valence transition or the valence crossover, which is ubiquitous in the rare-earth based ACs and QCs.
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Instrumentation and Detectors
Beam Spill Structure Measurements at CEE Using the T0 Detector
Shuaike Lv, D. Hu, Dayu Yin et al. (+29 more)
The Cooling Storage Ring External-target Experiment (CEE) at the Heavy Ion Research Facility in Lanzhou uses a slow-extracted heavy-ion beam whose temporal profile directly affects detector occupancy. The existing CEE T0 detector, originally designed to provide the event start time, is extended in this work to measure the spill structure immediately upstream of the fixed target. The detector consists of a 0.8-mm-thick EJ-200 plastic scintillator read out by 16 silicon photomultipliers at each end. The SiPM signals are conditioned and discriminated by the NINO front-end electronics, and the resulting timing signals are recorded using an FPGA-based time-to-digital converter. In laboratory tests, with the
laser trigger set to its maximum available repetition frequency of 100~MHz, the recorded T0 hit-rate distribution was concentrated around 100~MHz. During the June 2024 beam test with 350-MeV/u Kr ions, the accelerator team varied several operating settings, including RF-KO, sextupole, and feedback settings, while T0 independently recorded the corresponding spill profiles. An empirical representation was used to extract the rise, plateau, and fall durations from the stored profiles. The plateau duration was used as the primary comparison metric while accelerator stability and RF-system load were also considered. The measurements clearly distinguished the spill-profile responses associated with different accelerator settings. The spill obtained with the selected settings exhibited a more nearly rectangular envelope than the initial profile, although residual fluctuations and a terminal spike remained. These results demonstrate that the existing CEE T0 detector can provide independent beam-structure information during accelerator tuning.
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All authors Shuaike Lv, D. Hu, Dayu Yin, Haoqian Xu, Herun Yang, He Zhao, JiaJun Qin, Junfeng Yang, Juan Ruan, Jie Li, Ke Sun, Lei Zhao, Lijun Mao, M. Shao, Min Li, Meitang Tang, Shiya Huang, Tong Liu, Tingting Hou, Weilong Li, Wenwen Ge, XiangLun Wei, Yuhong Yu, Yingjie Zhou, Yiding Zhao, Yapeng Zhang, Zhoubo He, Zhijie Li, Zixuan He, Ziyang Wei, Zhiyu Sun, Zhengyang Sun
Strongly Correlated Electrons
Real-Time Relaxation Dynamics of Dark Excitons in Mirror-Symmetric Monolayers
Rishabh Saraswat, Mantasha Ansari, Rekha Verma et al. (+1 more)
Symmetry governs which
exciton-
phonon (exc-ph) scattering channels can exist, but not which a relaxing
exciton actually uses. Combining group theory with ab initio many-body perturbation theory, we derive the mirror parity $\sigma_h$, of finite-momentum
excitons in planar $D_{3h}$ monolayers, and form exact exc-ph selection rules that hold across the whole Brillouin zone. The parity of the lowest
exciton band changes across a closed contour. The even
phonons connect states of the same parity, while odd
phonons connect states of opposite parity. We use these rules to compute
exciton linewidths and we solve the real-time Boltzmann transport equation for monolayer GaN as the test case and
benchmark it against monolayer hBN.
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All authors Rishabh Saraswat, Mantasha Ansari, Rekha Verma, Sitangshu Bhattacharya
Optics
Matrix-free numerical continuation of the Ikeda map in passive Kerr resonators
Yuandi Xu, Pengxiang Wang, Jianxing Pan et al. (+2 more)
We introduce a
matrix-free numerical continuation framework for the Ikeda map of coherently driven passive Kerr resonators. The framework traces solution branches and evaluates their linear stability without explicitly assembling the full Jacobian
matrices, using a unified formulation for states that recur after one or multiple round trips. We resolve stable and unstable branches of modulation-instability patterns and temporal cavity
solitons, and uncover period-doubled homogeneous states and associated multi-round-trip dynamics that are absent from the standard Lugiato-Lefever equation (LLE). For period-1 states, the Ikeda map and the LLE show close agreement in the high-finesse regime, while their branch-existence intervals increasingly deviate as the finesse decreases. These results demonstrate that direct continuation of the unaveraged round-trip map can capture nonlinear states and multi-round-trip dynamics beyond the mean-field description, providing a systematic framework for bifurcation and stability analysis of Kerr resonators without relying on the averaged LLE.
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All authors Yuandi Xu, Pengxiang Wang, Jianxing Pan, Haisu Zhang, Gang Xu
Chemical Physics
NucleoNet: A Nuclear-Aware Determinant Ansatz for Multi-Geometry Neural Variational Monte Carlo
Qiao Gao, Yang Huang, Enze Hou et al. (+3 more)
Neural-network variational Monte Carlo provides an accurate route to solving the electronic Schrödinger equation, but many neural wavefunctions are optimized for a single nuclear geometry, requiring separate calculations to map out a potential energy surface. We introduce NucleoNet, a nuclear-aware determinant ansatz in which electrons and
nuclei form a unified particle set propagated through a shared electron–
nucleus backbone that jointly evolves one-particle and two-particle representations.
Nuclei carry learned representations that evolve alongside the electronic representations and condition orbital construction, while antisymmetry is imposed only by electronic determinants. On
equilibrium small-molecule
benchmarks, NucleoNet achieves accuracy comparable to established neural-wavefunction baselines with substantially fewer parameters. For each molecular system, a single model optimized jointly across geometries describes the N$_2$ dissociation curve, Li displacement in LiCN, and the ethane and formamide minimum-energy paths for bond dissociation. Sparse-geometry training generalizes to unseen geometries for N$_2$ and LiCN without further optimization, and N$_2$ ablations show that nuclear streams substantially improve this interpolation. These results show that a compact wavefunction with jointly evolved nuclear representations can describe the geometries of a molecular system with a single set of parameters.
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All authors Qiao Gao, Yang Huang, Enze Hou, Yuzhi Liu, Jingrun Chen, Han Wang
Optics
Silent breakdown of the perturbative polarization expansion in the terahertz regime
Yao Lu, Jiawei Zhang, Qiang Wu et al. (+1 more)
Nonlinear optics expands the polarization in powers of the drive and retains only the lowest-order terms. This truncation is safe at optical frequencies, where the convergence field lies far above the damage threshold. In the terahertz regime,
phonon polaritons enhance the nonlinear susceptibilities by orders of magnitude, lowering the convergence field into the sub-damage range and opening a window in which the expansion fails while the
crystal remains recoverable. We term this window silent breakdown. At resonance, the nearest singularities of the driven
lattice mode are a complex-conjugate pair of branch points below the multistability threshold, so the response remains smooth and single-valued even though the $\chi^{\left( n \right)}$ description fails. The convergence field scales as $Q^{-3/2}$, so sharpening a resonance enhances the nonlinearity but narrows the range over which the expansion applies. It follows from the mode shift $S$ alone, $E_{\mathrm{conv}}=E_{\mathrm{ref}}(3\sqrt{3}QS)^{-1/2}$, giving 2$\sim$9 MV/cm for $\mathrm{LiNbO}_{3}$. Since resonant enhancement is central to terahertz nonlinear optics, this boundary defines the field range over which susceptibility-based descriptions are quantitatively reliable.
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All authors Yao Lu, Jiawei Zhang, Qiang Wu, Jingjun Xu
Quantum Physics
Quantum Information-Theoretic Analysis of Optical Fiber Sensing via Stimulated Brillouin Scattering
Kiran Adhikari and Janis Nötzel
Stimulated Brillouin scattering (SBS) is a powerful mechanism for distributed sensing in optical fibers, as the Brillouin response is highly sensitive to local material parameters. Assuming the input probe is a
quantum state, we develop a
quantum-information-theoretic framework for SBS-based fiber sensing and intrusion detection. Starting from a linearized opto-acoustic
Hamiltonian, we derive an effective input-output relation for a short fiber segment. We then model each fiber segment as a single-mode bosonic Gaussian channel and the entire fiber as a cascade of
quantum channels. We then compute the
quantum Fisher information for general SBS-dependent parameters and identify optimal measurement settings to achieve the
quantum limit, comparing them with receiver-constrained strategies such as heterodyne detection and
photon counting. In addition, we propose an adaptive approach that achieves first-order asymptotic optimality and provides a novel second-order correction to address preliminary miscalibration. As an application, we apply the framework to the fiber-tapping detection problem.
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Instrumentation and Methods for Astrophysics
An Ultraviolet Instrument on the Habitable Worlds Observatory: Considerations and Capability Trades on the Multi-Object, Integral-field, and High-resolution modes of a potential UVI
Brian Fleming, Kevin France, Dmitry Vorobiev et al. (+4 more)
The Habitable Worlds Observatory (HWO) is NASA's next-generation astrophysics platform, delivering transformative capability in the search for life and study of the origins of the universe. Amongst the instruments under consideration for HWO is a multi-purpose ultraviolet spectrograph and imager that provides a deep toolbox for some of the most pressing science investigations of the next several decades. In this paper, we present a basic draft model of a potential UVI, including a multi-object spectrograph, far ultraviolet imager, high resolution spectrograph, and integral-field spectrograph. The draft designs for these channels of the UV instrument serve as a basis for a general discussion of the instrument architecture and design challenges, while also identifying potential trades, enhancements, and other considerations that the HWO project will need to address as it moves into the formulation phase. We conclude with a presentation of several scientific simulations that have helped guide the capabilities of the draft design. This paper is intended to serve as a summary of UV instrument modes, technology, and potential design ahead of planned instrument studies in the late 2020's, and then Phase A in the early 2030's.
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All authors Brian Fleming, Kevin France, Dmitry Vorobiev, Jeanette Donber, Eric Frater, Thomas Delker, Vicki Herde
High Energy Physics (Phenomenology)
Spectroscopy of $ncnc\bar{c}$, $nnnn\bar{c}$, and $nnnc\bar{c}$ pentaquarks within the framework of Regge phenomenology
Vandan Patel and Ajay Kumar Rai
We investigate the mass spectra of the \(ncnc\bar{c}\), \(nnnn\bar{c}\), and \(nnnc\bar{c}\) pentaquark systems, where \(n\) denotes a light \(u\) or \(d\)
quark, within a leading-order linear Regge approximation. The extension of the baryon intercept and inverse-slope additivity relations to these systems is implemented as a minimal cluster-additive ansatz for compact color-antitriplet diquarks, rather than assumed to be an exact QCD relation. By analyzing the corresponding trajectories in the \((J,M^2)\) plane, we first determine the allowed mass range of the ground-state \(ncnc\bar{c}\) pentaquark and extract the associated Regge parameters. Using these inputs, we estimate the mass intervals of the excited states of the \(ncnc\bar{c}\), \(nnnn\bar{c}\), and \(nnnc\bar{c}\) systems. We also obtain analytical mass-inequality relations. The resulting spectra exhibit a systematic ordering with increasing total
spin and orbital excitation along the Regge trajectories. We further compare the predicted states with selected kinematically compatible
meson–baryon thresholds as a qualitative guide to possible nearby channels. Our results provide a useful reference for future theoretical studies and may serve as a guide for experimental searches and
spin-parity assignments of pentaquark candidates in the open- and hidden-charm sectors.
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Instrumentation and Detectors
CNN-based Position Reconstruction for the T0 Detector in the HIRFL-CSR External-target Experiment
Shuai-Ke Lv, D Hu, M Shao et al. (+2 more)
The T0 detector provides the event start time for the HIRFL-CSR external-target experiment, and its multi-channel readout signals also contain 2D position information of incident particles. In the CEE experiment, the dedicated beam-profile detector has a rate capability of only ~1 kHz, far below the beam event rate of up to 1 MHz, so it cannot provide real-time beam-spot monitoring under high-rate data-taking or an event time reference. To fill this gap, this work studies a CNN-based position reconstruction method that enables the T0 detector to provide both start time and beam-spot information. The over-threshold times and time-over-threshold (TOT) values from 32 SiPM channels are reorganized into a geometry-preserving input tensor. Time features are corrected by event-wise mean-time subtraction, and TOT features are normalized by an event-wise trimmed mean before feature standardization. A customized CNN directly regresses the incident coordinates. Training and validation samples are built with Geant4 simulation and waveform digitization, and the method is evaluated using a pulsed-
laser scanning data set with known position labels. On independent test sets, the residual standard deviations for uniformly distributed planar simulation data are about 1.11 and 1.04 mm in x and y. For the discrete
laser-scanning geometry, the resolutions are about 2.36 and 1.34 mm in simulation and 2.42 and 1.41 mm in experiment. The trained model is applied to CEE zero-field beam data collected at the Institute of Modern Physics, Lanzhou, in January 2026, and a 2D beam-spot distribution is reconstructed. These results show the T0 detector's potential as a high-rate beam-spot monitor while retaining its role as an event start-time detector.
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All authors Shuai-Ke Lv, D Hu, M Shao, Yingjie Zhou, Yiding Zhao
Earth and Planetary Astrophysics
The Neptunian Final Parsec Problem: How Inertial Waves Enable Neptunes and Gas Giants to Survive Tidal Migration
Tim Hallatt, Adrian J. Barker and Sarah C. Millholland
Observations indicate that some hot Neptunes and Jupiters underwent high eccentricity migration (HEM). A longstanding issue facing HEM theory remains, however: in order to shrink their orbits by ${\sim}1{-}2$ orders of magnitude,
planets must dissipate ${\gtrsim}10{\times}$ more orbital energy than is contained in their structural binding energy. Previous work suggests that excitation of
planets' fundamental modes (”$f$-modes”) at very high eccentricities, $e{\sim}$0.99, can shrink semi-major axes by ${\sim}$an order of magnitude (${\sim}5{\rightarrow}0.5$ au) while safely bleeding tidal energy to space. We examine how
planets traverse the remaining order of magnitude in orbital shrinkage, $a{\sim}$0.5${\rightarrow}$0.05 au, which still poses a danger for Neptunian
planets due to their lower binding energies (their ”final parsec” problem). To assess whether tidally-migrating Neptunes balance their energy budgets, we perform coupled orbit/structure calculations tracking their frequency-dependent tidal response under inertial waves (IWs). We show that tidal radius inflation at moderate eccentricities sweeps Neptunes' fundamental modes back into resonance with tidal forcing; only a small amount of tidal heat relative to a Neptune's binding energy is needed to drive this $f$-mode excitation. This excitation of Neptunes' $f$-modes may offer a route to safe circularization, provided the $f$-mode dissipates without harming the
planet. In contrast, eccentric gas giants ($e{\sim}0.9$) circularize without drama over ${\sim}$Gyr. Our theory predicts that warm Neptunes on a HEM track ($a{\gtrsim}0.1 \ \mathrm{au}, \ e{\gtrsim}0.8$) should be rare, in opposition to warm gas giants and lower eccentricity Neptunes. Observational confirmation of our predictions would constrain the interior structures of Neptunian
planets via tidal theory.
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Soft Condensed Matter
Ionic liquid/PDMS coated nanostructured ZnO surfaces for superior antibacterial activity
Anushika Rohilla, Ajit Seth, Mayank Bharadwaj et al. (+2 more)
The development of nanostructured antibacterial surfaces has gained significant
attention due to the urgent need to combat bacterial colonization and biofouling across food, healthcare, and marine sectors. Among functional metal oxides, zinc oxide (ZnO) nanostructures are particularly promising owing to their rich morphology, favourable physicochemical attributes, and intrinsic bactericidal properties. Here, we utilize a green, eco-friendly Hot Water Treatment (HWT) method to fabricate dense ZnO nanorod arrays on zinc substrates. To overcome the practical limitations and challenges of conventional antibacterial coatings, such as poor operational stability, cytotoxicity, and the risk of antimicrobial resistance, we developed a durable hybrid coating composed of an imidazolium-based ionic
liquid stabilized with polydimethylsiloxane. The resulting hybrid-coated nanostructured surfaces exhibit superior antibacterial efficacy against Escherichia coli through a combination of topography-induced mechanical strain and membrane disruption.
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All authors Anushika Rohilla, Ajit Seth, Mayank Bharadwaj, Rumal Singh, Sajal K Ghosh
Materials Science
High-Throughput Discovery of Chiral Carbon-Boron Semimetals with Weyl Topology and Phonon-Mediated Superconductivity
Lizhou Yang, Wenneng Zhao, Ye Yang et al. (+9 more)
Chiral
crystals provide a natural platform for unconventional topological
fermions, while light-element carbon–boron frameworks are promising for
phonon-mediated superconductivity owing to strong covalent bonding and high
phonon frequencies. Here, we combine Wyckoff-position-based structure generation with high-throughput first-principles calculations to search for C–B
crystals in selected hexagonal chiral space groups. Starting from 972 generated $\mathrm{C}_m\mathrm{B}_n$ structures ($m,n=1\text{--}4$), successive filters based on energetic stability, dynamical stability, electronic
metallicity, topological band features, and thermal stability identify six stable candidates: $(\mathrm{C}_3\mathrm{B}_2)_8$, $(\mathrm{C}\mathrm{B}_2)_3$, $(\mathrm{C}\mathrm{B}_4)_6$, $(\mathrm{C}_3\mathrm{B}_2)_6$, $(\mathrm{C}_2\mathrm{B}_3)_6$, and $(\mathrm{C}\mathrm{B}_2)_6$. These materials host diverse topological semimetal states near the Fermi level, including charge-one, charge-two, and charge-three Weyl points, nodal rings, and nodal-surface states. Notably, $(\mathrm{C}_3\mathrm{B}_2)_8$ exhibits screw-
symmetry-protected charge-three Weyl points and strong electron–
phonon coupling, yielding a McMillan transition temperature of $31.1\,\mathrm{K}$ for the Coulomb pseudopotential parameter $\mu^* = 0.10$. In addition, $(\mathrm{C}\mathrm{B}_2)_3$ hosts multiple charge-one Weyl points and pronounced anisotropic multiband superconductivity revealed by fully anisotropic Eliashberg calculations. These results extend the materials scope of topological semimetals with
phonon-mediated superconductivity to chemically designed chiral light-element structures.
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All authors Lizhou Yang, Wenneng Zhao, Ye Yang, Weiwei Chen, YongKeat Chan, Chen-Hao Lv, Qing-Bo Liu, Yujia Xiang, Xinming Qin, Zedong Li. Weiyi Wang, Jinlong Yang, Wei Hu
Mesoscale and Nanoscale Physics
Vacuum-field-mediated Landau-level reconstruction in a cavity-coupled two-dimensional electron gas
Zi-Heng Zhu and Yu Chen
We study a two-dimensional electron gas in the integer
quantum Hall regime coupled to a single spatially modulated cavity mode in the static off-resonant limit. Retaining both paramagnetic and diamagnetic contributions on equal footing, we derive a gauge complete single-particle
Hamiltonian in which virtual
photon exchange generates a periodic kinetic renormalization and a diamagnetic scalar potential. Both terms transfer momentum by $2k_0$ and displace guiding centers by $\Delta X=2k_0\ell_B^2$, forming a finite-$k_0$ momentum ladder. Diagonalizing the strip
Hamiltonian, we find that the ladder reconstructs the Landau-level band structure and redistributes, rather than multiplies, the associated chiral edge states. Occupied-subspace Chern numbers remain $C_\nu=\nu$ for $\nu=1,2,3$ throughout $0\le\lambda_{\mathrm{cav}}\le 0.5$, while the bulk gaps decrease without closing. Strip Kubo responses show cavity-induced displacements of the Hall-step energies; at finite width the plateau heights are noninteger and approach the integers as $L_x$ increases. The ladder is spectrally resolved at $k_0\ell_B=0.5$ and collapses at $k_0\ell_B=0.1$. These results isolate a spatially local, finite-$k_0$ momentum ladder as a clean-system mechanism by which a structured
vacuum field reconstructs
quantum Hall spectra and strip transport without changing the integer
topology, complementary to cavity-mediated all-to-all hopping.
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High Energy Physics (Phenomenology)
Predictions for neutron-tagged Coulomb dissociation in ultraperipheral Ru+Ru and Zr+Zr collisions
Huda Nasrulloh, Xinbai Li, Zebo Tang et al. (+4 more)
The photonuclear response reflects nuclear structure and the dynamics of excitation and decay, with
neutron-emission channels retaining information that can be obscured in inclusive dissociation yields. We calculate specified-side and mutual
neutron-tagged Coulomb-dissociation cross sections in ultraperipheral $^{96}_{44}\mathrm{Ru}+{}^{96}_{44}\mathrm{Ru}$ and $^{96}_{40}\mathrm{Zr}+{}^{96}_{40}\mathrm{Zr}$ collisions at $\sqrt{s_{\mathrm{NN}}}=200~\mathrm{GeV}$ using an impact-parameter-dependent equivalent-
photon framework with photonuclear inputs from TALYS calculations and ENDF evaluations. Across the two input sets, the predicted Ru/Zr ratios span $1.54$-$1.71$ for exact $1n$ and $2.49$-$3.09$ for $1n1n$, while inclusive $Xn$ (at least one
neutron) and $XnXn$ ratios remain near unity at $0.96$-$0.99$ and $1.05$-$1.10$, respectively. The one-
neutron ratios lie well above the corresponding flux-only $Z^2$ and $Z^4$ charge-scaling references, reflecting differences in the low-energy one-
neutron response that are amplified by mutual tagging. This
topology hierarchy identifies
neutron-tagged isobar ratios as sensitive probes of photonuclear response, revealing response differences hidden in inclusive dissociation. These calculations also provide
neutron-emission inputs for
neutron-tagged vector-
meson photoproduction in isobar collisions.
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All authors Huda Nasrulloh, Xinbai Li, Zebo Tang, Kaiyang Wang, Luobing Wang, Xin Wu, Wangmei Zha