Papers

Motivated by programmable tweezer arrays, we develop an exactly solvable shape-space theory for near-equilateral atomic trimers. The Higgs oscillator on Kendall's shape sphere gives a nonresonant spectral lattice whose fixed-angular-momentum relative-stationary minimizers are supported on two adjacent admissible sites. These symmetry-selected doublets are separated from higher relative-stationary branches by a finite branch gap. With phase-coherent shape-mode driving and Rydberg-mediated conditional phases, they furnish a candidate route to geometric qubits and entangling operations.

We investigate gravitational lensing in Kerr spacetime in the presence of a modified photon propagation law arising from higher-curvature effective field theory corrections. Adopting a deformed dispersion relation, we analytically derive the deflection angle and the propagation time delay for null trajectories in a rotating background. We show that the modified propagation leads to explicit and calculable deviations from the standard Kerr predictions, affecting both the bending angle and the time delay. These corrections exhibit a nontrivial dependence on the black hole spin and are expected to become more relevant in the strong-field regime. In particular, near the photon region-where the spin-dependent geometry influences photon trajectories-such effects may play a role in shaping observable propagation features. Our results establish a concrete and systematic framework to quantify deviations from standard photon propagation in gravitational lensing. They further indicate that observables such as relativistic image separations and time delays provide a potential avenue to probe ultraviolet corrections to gravity in strong-field environments.

Quantum relaxometry based on nitrogen-vacancy (NV) centers in diamond is an easy-to-use technique that detects magnetic noise by measuring the longitudinal relaxation of NV centers. It is favored in chemical and biological applications due to the robustness against imperfect spin control. By tuning the energy level, NV relaxometry can detect magnetic noise generated by other spins and obtain magnetic resonance spectra through cross relaxation. However, the inhomogeneous broadening of NV centers greatly limits the spectral resolution of cross-relaxation spectra. Here we demonstrate a hole-burning technique to remove the inhomogeneous broadening. We utilize a weak pump field to deplete specific NV centers during the relaxation measurement, which contribute a reverse signal in the cross-relaxation spectra with a much narrower linewidth. Our method retains the convenience and sensitivity of NV relaxometry, opening up new avenues for high-resolution magnetic resonance spectroscopy in complex scenarios.

Conical geometries provide the standard description of disclinations, but they concentrate the curvature at a singular apex. We introduce a Yukawa-type regularization that replaces this singularity by a smooth curvature distribution while preserving the asymptotic topology of the defect. Exact expressions are obtained for the conformal factor, curvature, and enclosed topological charge. The resulting geometry exhibits a scale-dependent topological charge and a corresponding radius-dependent holonomy, establishing a direct connection between distributed curvature and geometric phases. We further investigate the dynamics of massless Dirac quasiparticles in this background and show that the regularized core modifies the spin connection while preserving the asymptotic topological signature of the defect. These results provide a finite-core extension of the conventional conical description and offer a natural framework for studying geometric and topological effects in graphene-like systems.

Shortcuts to adiabaticity (STA) is a common protocol to realize high-fidelity and robust quantum control in various quantum systems. To date, STA has been widely applied in two- and three-level systems, whereas designing feasible strategies to achieve perfect quantum state engineering in multi-level systems still remains a challenging task. Here, we propose to use counterdiabatic (CD) driving and time-rescaling (TR) methods to construct multi-state stimulated Raman shortcut-to-adiabatic passage protocols for realizing robust and fast population transfer in chainwise-connected five-state systems. The first protocol is implemented by initially reducing the original five-state system to an equivalent two-state counterpart, and then designing the corresponding driving field by combining CD driving and unitary transformation. Further, we introduce the TR method to optimize the first protocol and thus offers an alternative solution. Numerical calculations show that both protocols can achieve complete population transfer and effectively suppress transient populations of all intermediate states. Compared with the first protocol, the optimized second exhibits better performance within a shorter evolution time.

I rivisit the history of the first matter-antimatter collider built in Italy in 1960 and carried to success through an inter-European collaboration with France, underlying the foundational role of the Austrian born theoretical physicist Bruno Touschek. Touschek's life path through Europe before and after World War II is briefly recalled. The role of CERN in jump-starting this international collaboration between the Frascati National Laboratories in Italy and the Orsay Linear Accelerator Laboratory in France, is highlighted through historical documents, and contributions from interviews with the main protagonists of Touschek's game-changing proposal.

This work proposes a compact and hardware-efficient frequency- and radiation-pattern-reconfigurable antenna (FPRA) for passive multi-target direction-of-arrival (DOA) estimation using a single receive RF chain. The antenna consists of a sectorized circular patch loaded with 16 PIN diodes. By switching the diode states, the current-concentration boundary on the patch is shifted, enabling reconfiguration of both the operating frequency and radiation pattern. With a single receive RF chain, the proposed antenna achieves beam scanning from -40 degrees to 40 degrees and provides multiple operating frequencies across the S- and C-bands. Based on these reconfigurable observation states, radiation-pattern switching is used to emulate the spatial sampling of a conventional antenna array, while multi-frequency observations introduce phase diversity to reduce the correlation among echoes from multiple passive targets illuminated by the same transmitter. Experimental results demonstrate that the combined virtual spatial sampling and frequency diversity enable passive multi-target DOA estimation without a conventional antenna array or multiple receive RF chains. The proposed FPRA offers a compact and hardware-efficient sensing solution for future integrated sensing and communication (ISAC) systems.

We investigate the existence and dynamics of two-dimensional solitary waves in a quantum droplet environment described by the extended Gross-Pitaevskii equation featuring logarithmic mean-field and Lee-Huang-Yang interactions. In the modulationally stable regime of the background, we employ suitable multiscale asymptotic methods to derive effective nonlinear integrable models corresponding to the Kadomtsev-Petviashvili and Davey-Stewartson equations. Based on these reduced models, we construct approximate analytical solutions describing line solitons, algebraically localized lump solitons, ring solitons, and exponentially localized dromions embedded on the droplet background. The dynamical robustness of these solutions is monitored through numerical simulations. Line, lump and ring solitons stay closest to the theoretical predictions, although progressively deviate due to the emergence of small-amplitude radiation, while dromions depart from their analytical waveform the most, although they roughly maintain their shape. Our results unveil unprecedented multidimensional soliton solutions in models featuring the competition of mean-field and quantum fluctuations and as such are amenable to current ultracold atom experiments.

Strategy learning governs the evolution of collective cooperation in multi-agent systems. Although evolutionary outcomes depend strongly on the information available to agents during strategy learning, most studies treat both the source and amount of that information as fixed over time. In reality, however, individuals are continually exposed to external information that varies over time. Here we develop a general framework for evolutionary dynamics with temporal information, which uses temporal networks to characterize dynamic changes in information available for strategy learning, with time-varying connections determining each agent's information state. Across synthetic and empirical networks, we find that temporal information consistently promotes cooperation relative to their static counterparts. We further demonstrate that this advantage becomes more pronounced as temporal networks become sparser. This pattern arises because sparsification amplifies information heterogeneity among agents, creating unequal access to learning information that can facilitate the spread of cooperative strategies, in sharp contrast to static information formulations where heterogeneity often suppresses cooperation. Guided by this insight, we develop an interpretable algorithm that substantially enhances cooperation across diverse networks by generating learning networks with tunable heterogeneity. Our results identify temporal information as a realistic and broadly applicable mechanism for promoting collective cooperation.

Observations reveal a pronounced deficit of white dwarfs (WDs) in open clusters (OCs) relative to theoretical expectations, suggesting that a significant fraction of WDs may have escaped from their parent clusters after formation. In this work, we perform a systematic search for escaped WD candidates from OCs by back-tracing the motions of WDs and star clusters from Gaia DR3 catalogs. We identify 476 candidate WDs with kinematics consistent with having escaped from one of 175 OCs. A control-field Monte Carlo (MC) test yields a contamination rate of 87.6% +/- 4.3%. Given this high contamination rate, we filter the candidates by ensuring each WD's total age is consistent with its host cluster age, thereby establishing a more reliable follow-up sample of 109 stars. The excluded candidates with anomalous ages are more likely field interlopers or products of accelerated binary evolution. Among these, the low-mass regime exhibits a clear excess over expected field binary merger rates, whereas the high-mass regime remains broadly consistent with binary population synthesis predictions. Finally, comparing escaped WDs with cluster properties, absolute escape counts appear limited by Gaia's distance-dependent incompleteness. The normalized escape fraction shows little dependence on cluster age, possibly favouring WD loss near formation over gradual evaporation, but is strongly anticorrelated with cluster mass, plausibly because deeper potential wells of massive clusters retain more of their WDs.

We investigate potential singularities in isotropic cosmological models featuring a time-varying speed of light and the gravitational constant. The governing field equations generally simplify into two-dimensional systems, subject to analysis through dynamical systems techniques within phase space and the application of asymptotic splitting methods. In the broader context, our findings reveal the existence of initially expanding closed models that undergo subsequent recollapse towards a future singularity, and open universes exhibiting perpetual expansion into the future. The specific characteristics of these singularities are also expounded upon.

We develop a density-functional theory for solutions of associating polymers where attractions among charged monomers (stickers) are represented by local binary degrees of freedom, which are randomly placed along the chains. Extending the original Garel and Orland's field-theoretic scheme for single-chain systems to an ensemble of interacting chains, we give the exact formulations of the model in both cases of annealed and quenched distributions of charges which we solve at the mean-field level. The solution produces qualitatively different free energy functionals. In the annealed case, the theory naturally yields a nontrivial scalar order parameter for the fraction of bonded sticker monomers and a self-consistent mass-action law at the saddle point. By contrast, in the quenched case no independent bonding order parameter emerges and the main effect is a renormalization of the effective two-body and three-body interaction parameters. The formulation is microscopic at the Hamiltonian level and, within the same field-theoretic framework, provides a systematic starting point for fluctuation corrections beyond the mean-field approximation.

We present a comprehensive study of the current-phase relation of the Josephson junction in a holographic superfluid ring, realized from the stochastic and non-equilibrium dynamics according to the Kibble-Zurek mechanism. By employing a spatially modulated charge density to engineer a weak link, the current-phase relation is investigated in a range of geometric and thermodynamic parameters. The seminal sinusoidal relation between the current and the phase emerges periodically due to the compact shape of the geometry. We also identify the relations between the critical current and the geometric parameters of the junction: the width, steepness and depth. Furthermore, we demonstrate that the critical current exhibits a characteristic exponential decaying against the final temperature, reflecting the thermal degradation of the order parameter in a strong-coupling regime. Our results establish a robust framework for holographic Josephson devices, offering experimentally testable predictions for the non-equilibrium dynamics of high-$T_c$ superconductors.

Variational Quantum Algorithms (VQAs) are a leading paradigm for near-term quantum computing, yet their training suffers from sensitivity to circuit depth, initialization, and landscape pathologies such as barren plateaus. We study progressive depth training (PDT) – a layerwise curriculum that trains a shallow circuit before appending new layers – and identify a fundamental obstacle: fixed entangling gates (CNOTs) in hardware-efficient ansätze cause initialization shock, an energy spike when new layers are added. We propose identity-paired progressive depth training (IP-PDT), which appends forward/inverse block pairs – each consisting of a standard rotation$+$CNOT block followed by its reverse – that compose to the identity at initialization. Because the adjacent CNOT rings cancel, the effective circuit retains only a single entangling layer surrounded by overparameterized local rotations. We prove a simple Reachable Set Saturation Theorem: under this construction the variational manifold expands exactly once (when post-entangler rotations are first introduced) and then saturates; all subsequent depth increases provide pure overparameterization of single-qubit unitaries. Despite this saturation, progressive addition of rotation parameters can continue to improve optimization outcomes – a phenomenon we term trainability beyond expressibility. We formalize IP-PDT as a continuation method on nested manifolds, prove monotone energy guarantees under an acceptance rule, and connect energy error to ground-state fidelity through spectral-gap inequalities. A detailed resource analysis shows that IP-PDT achieves lower total gate cost than both baselines by eliminating most CNOT gates.

The region near the interface between cortical bone and the medullary cavity (the endosteal surface) is of particular interest for the early detection of osteoporosis. This region is typically the first to exhibit signs of unbalanced remodeling (enlarged pores and increased surface roughness). In this study, we analyze ultrasound reflection at the endosteal surface to introduce a novel potential biomarker of cortical bone health based on specularity. Our hypothesis is that increased pore size and surface roughness enhance ultrasound scattering, thereby reducing specular reflection. We reconstruct maps of specularity by combining a signal processing technique initially designed to enhance specular reflectors in soft tissues with a beamforming technique that accounts for refraction at bone soft tissue interfaces. Specularity values (between 0 and 1) quantify the similarity between received signals and signals from an ideal specular reflector. Using numerical simulations and ex vivo measurements with a 2.5 MHz phased array we highlight a strong relationship between specularity and bone microstructure, as assessed by high-resolution micro-computed tomography. Among 12 regions of interest (ROI) in the femoral bone of three donors, 8 ROIs without large pores showed high specularity (>0.5) in over 50% of pixels, in contrast to 4 ROIs with signs of extensive remodeling. Both pore volume fraction and pore size were strongly associated with specularity. In simple linear regression analyses, each parameter individually explained 84% of the variability in specularity. These findings suggest that specularity reflects bone microstructure and may potentially serve as a sensitive marker for identifying cortical bone degradation near the endosteal surface.

In Part I of the companion paper [Ref Part I], we have extensively discussed about the creation of quasi-stationary ion scale (QSIS) inhomogeneity using a constant frequency external drive at ion-acoustic time scales, resulting in ion trapped particle instability (ITPI), wave-wave mode coupling interaction and energy cascading. QSIS thus formed is perturbed by applying small amplitude electron acoustic (EA) mode leading to the several key plasma response features. In this Part II, using electrostatic, unbounded, OpenMP Vlasov-Poisson solver i.e VPPM-OMP 1.0, we have investigated the formation of various phase space vortices (PSV) (generated using two step or one step time dependent downward frequency chirping drives) in the presence of background QSIS inhomogeneity obtained in Part I. In addition, we have also performed one to one comparison of individual cases with their homogeneous counterparts with exact simulation parameters. In presence of QSIS inhomogeneity, we have observed interesting phenomenon such as early onset of Langmuir (LAN) mode, suppression of PSV sizes, omission of PSVs when compared to the homogeneous cases. Also, for different two step or one step downward chirp perturbation cases, particle trapping or untrapping fractions and its response to the increasing chirp intervals are respectively reported.

We study thermal transport across copper-graphene-copper interfaces using Non-Equilibrium Molecular Dynamics (NEMD), focusing on the influence of finite domain length and domain configuration, including lattice initialisation and associated graphene wrinkling, on the predicted thermal conductivity and Kapitza resistance. In the literature, NEMD simulations identified trends in the Kapitza resistance of graphene-copper interfaces. However, the simulation outcomes and reliability may depend heavily on configuration choices that are underexplored in the literature. We identify a strong sensitivity of the Kapitza resistance to domain configuration choices that affect the lattice constants and atomic density. We show that two conventional lattice initialisation strategies yield a factor of two difference in the Kapitza resistance, despite differences of only a few per cent in the lattice parameters. This behaviour is accompanied by strain-dependent shifts in the graphene and copper phonon spectra, and by increased phonon overlap at lower strain. Counter to conventional expectations, greater phonon-mode overlap coincides with higher Kapitza resistance, showing that spectral overlap alone cannot capture the interfacial heat-transfer dynamics. We suggest that in lattices initialised with lower residual strain, a damping boundary layer develops near the interface, and increases thermal resistance, as indicated by increased local structural disorder and local spectral broadening over a wider interfacial region. Beyond strain- and density-related effects associated with the lattice constants, Kapitza resistance shows no significant dependence on domain length or boundary temperature enforcement in this study. By contrast, the copper lattice conductivity exhibits clear domain-size and temperature dependence, consistent with phonon mean-free-path limitations and supported by phonon spectral analysis.

Formation dynamics and stability starting from various phase space vortex (PSV) or Bernstein-Greene-Kruskal (BGK) structures i.e electron acoustic wave (EAW), Langmuir (LAN) waves is investigated in the presence of a quasi-stationary ion scale (QSIS) inhomogeneity using high resolution Vlasov-Poisson simulations with VPPM-OMP 1.0 solver. In a one dimensional, collisionless, periodic, unmagnetized plasma with kinetic ions and kinetic electrons, we first create a QSIS inhomogeneity using low amplitude electric field drive at ion acoustic (IA) frequency with k eq = mk min [where m = 2 is the mode number, k min corresponds to the longest scale in the system]. While creating QSIS inhomogeneity, we have demonstrated the existence of ion trapped particle instability (ITPI) which saturates as the amplitude of sideband modes become comparable to that of the primary nonlinear mode (quite analogous to the trapped particle instability in large amplitude electron plasma waves). Also, mode transition from m = 2 to m = 1 is observed during relaxation period due to the energy cascading process. Finally, an electron acoustic (EA) perturbation of scale k p = k min [m = 1] is applied on top of the QSIS inhomogeneity to determine its response in the presence of background ion scale inhomogeneity. Some key observations such as formation of transient PSV, wave-wave mode coupling interaction and various frequency generation alongwith comparative investigation with EA perturbation launched in the absence of ion scale inhomogeneity is also reported.

Three-body encounters are frequent events in stellar systems, intrinsically chaotic, and computationally costly to model with direct N-body integration. Predicting whether such encounters lead to binary formation is therefore challenging, particularly in large-scale simulations. We aim to develop an accurate and physically interpretable machine-learning model that predicts binary formation from the initial conditions of three-body encounters, to assess its reliability, and to identify the physical parameters that most strongly determine the outcome. We trained an XGBoost binary classifier on a balanced dataset of three-body scattering experiments computed with the REBOUND code and the IAS15 integrator. The input to the model consists of 30 physically motivated features describing the masses, energies, and kinematics of the initial configuration. The classifier achieves excellent performance on a balanced test set, with accuracy, precision, recall, and F1-score all above 0.94, and with ROC-AUC and PR-AUC values of 0.99. Feature-importance analysis shows that the outcome is governed primarily by the mass hierarchy and hardness ratio of the encounter, followed by velocity fraction and mass entropy. The predicted probabilities are well calibrated, with an expected calibration error (ECE) of 0.02. Inference is approximately 400 times faster than direct N-body integration. The model also generalizes well across encounter radii, although its performance decreases in the weak-interaction regime where binary formation becomes intrinsically rare. These results show that machine learning can provide fast, accurate, and physically interpretable predictions of binary formation in three-body encounters. Such models offer a practical complement to direct N-body simulations and may enable efficient probability estimates in large-scale simulations of stellar systems.

Estimating the iron abundance ([Fe/H]) of Classical Cepheids (CCs) is crucial both for validating the cosmic distance scale through the Period-Luminosity relation and for tracing the chemical evolution of young stellar populations. However, standard spectroscopic determinations are highly time-consuming, limiting their application to large or distant samples. This work delivers a practical, multi-band alternative by investigating whether light-curve Fourier parameters derived from Gaia mission photometry can serve as reliable proxies for [Fe/H]. Our reference sample comprises 398 fundamental-mode CCs from Gaia DR3 with high-resolution spectroscopic metallicities available in the literature, spanning a wide range of pulsation periods. Light curves in the G, G_BP, and G_RP bands were modeled with a truncated Fourier series to extract characteristic amplitudes, amplitude ratios, and phase differences. We implemented a replicated Random Forest algorithm as a feature selection tool to isolate the most predictive parameters based on their total increase in node purity. Using the selected features, we calibrated an empirical, multi-variable relation via linear regression, incorporating higher-order polynomial terms to capture complex morphological dependencies. The primary unweighted OLS model yields a residual rms of 0.213 dex and a Pearson correlation of 0.61. As an external validity check, we applied this calibration to large target samples of CCs in the Milky Way, LMC, and SMC. The resulting photometric metallicity distributions correctly reproduce the expected chemical enrichment history and peak values of the three galaxies, proving the reliability of this relation for population studies in the Gaia DR4 era.

We investigate the matrix model of two-color two-flavor QCD (matrix-QCD$_{2,2}$) in regimes with large baryon ($\mu_{_B}$), isospin ($\mu_{_I}$), and/or chiral ($c$) chemical potentials. In these regimes, the Hamiltonian simplifies considerably, making it possible to investigate the ground state for intermediate and strong Yang-Mills coupling. By diagonalizing the Hamiltonian using the variational techniques, we show that in regimes where $\mu_{_B}$ and $c$ (or $\mu_{_B}$ and $\mu_{_I}$) dominate, tuning the remaining parameters leads to quantum phase transitions (QPTs). These transitions form a complex web of phases, each of which has a ground state uniquely labelled by baryon number $B$ and isospin $I$. Several of these phases are LOFF-like, characterized by a ground state carrying non-zero spin and hence spontaneously breaking rotational symmetry. These results are consistent with older effective field theory predictions by Splittorff-Son-Stephanov \cite{Splittorff:2000mm}. The fermionic content of these LOFF-like ground states consists of spin-1 di-(anti-) quarks which are analogous to Cooper pairs. We compute the spin-fraction carried by the quarks and find that it constitutes a significant portion – in some cases nearly the entirety – of the total spin.

We consider the nearest-neighbor Edwards–Anderson Ising model on cubic boxes with random perturbations supported at the boundary. We prove that any perturbation admitting an energy envelope that is negligible compared with the volume, both in expectation and almost surely, leaves the limiting quenched specific free energy unchanged. For independent finite-variance bulk disorder in dimension at least two, an Efron–Stein estimate also yields almost-sure self-averaging along the full sequence of boxes. The hypotheses are verified for i.i.d. scalar surface fields, fixed random exterior spins, and periodic wrap-around bonds, with an $ O(L^{-1}) $ comparison of quenched means. The result concerns the specific free energy and does not assert convergence of finite-volume Gibbs measures.

Advancements in Natural Language Processing (NLP), whether on classical or quantum platforms, have predominantly focused on English due to its widespread use and abundant linguistic resources. Although English remains the most studied language in computational linguistics, Hindi, the third most spoken language worldwide after Mandarin, has received comparatively limited attention. Spoken primarily in India, Hindi differs significantly from English in its script, syntactic structure, and linguistic characteristics. Hindi uses the Devanagari script, exhibits rich morphological inflection, and follows a subject-object-verb (SOV) word order, unlike English's subject-verb-object (SVO) structure. Motivated by Hindi's linguistic complexity and its underrepresentation in Quantum Natural Language Processing (QNLP), we propose a grammar-aware QNLP pipeline for Hindi sentiment classification with a focus on sentential negation. We use a manually annotated Hindi sentiment dataset labeled as positive, negative, or neutral, and encode sentences using pregroup grammar types. Sentences are processed with Lambeq to generate quantum circuits using a novel negation-aware compositional grammar. Hybrid Quantum Neural Networks (HQNNs) are trained for both binary and ternary sentiment classification. Our results demonstrate effective sentiment classification and highlight the potential of compositional QNLP for morphologically rich languages.

Context. Binary-single encounters are particularly frequent in dense stellar environments, where they play a central role in shaping the dynamical evolution of their host systems. However, predicting their final outcomes remains an open question due to the intrinsic chaotic nature of the three-body problem. This challenge motivates the adoption of data-driven machine learning (ML) methods. Aims. We investigate whether ML can predict the final outcomes of binary-single encounters from initial conditions alone. Methods. We generated 5.8 million binary-single scattering simulations using the REBOUND N-body package with the IAS15 integrator. A cascaded binary classification strategy, comprising four sequential XGBoost classifiers, and a single multi-class model were trained on the synthetic dataset and compared. Results. The cascaded strategy outperforms the single multi-class model across all metrics. F1-scores for the cascaded models exceed 0.92, with precision-recall area under the curve (PR-AUC) values reaching 0.99, compared to 0.95 for the multi-class model. Feature importance analysis identifies encounter timescale, binary hardness, and mass ratio as key predictors. Misclassification analysis shows that prediction failures concentrate near chaotic boundaries where the outcome is sensitive to small perturbations. Speed benchmarks demonstrate that the cascaded models are up to 300 times faster than direct N-body integrations. However, all models fail to generalize to new datasets, highlighting a key limitation. Conclusions. This study demonstrates that, for any specific environment and data distribution, the proposed cascaded ML strategy provides a robust and rapid framework for predicting binary-single scattering outcomes.

In this article, the explicit $P-wave$ of the $\bar{\Lambda}_c\Lambda_c$ dibaryon states with the $J^{PC}=0^{-\pm}$ and $1^{-\pm}$ are studied via twelve interpolated currents. Results show that the positive and negative charge conjugations for the studied states do not have too much difference, the contribution of the gluon from covariant derivative of the current with $P-wave$ could be neglected. The numerical results of the masses of the $P-wave$ $\bar{\Lambda}_c\Lambda_c$ are high above the threshold of the two $\bar{\Lambda}_c$ and $\Lambda_c$ baryon constituents, $\bar{\Lambda}_c$ and $\Lambda_c$ are unlikely to form the bound molecules with explicit $P-wave$ . Pole residues of the related states are also calculated.

Conventional photonic doping schemes predominantly employ circular or rectangular dielectric dopants with zero topological charge, where the effective permeability can only be tuned through material selection and geometric scaling, resulting in limited design flexibility. In this work, topological structures are introduced into dielectric dopants by embedding internal holes to generate nonzero topological charge. Based on this concept, a theoretical model is established to describe the effective permeability of photonic doping systems with nonzero topological charge, and the underlying mechanisms governing topological-charge-dependent transmission are systematically elucidated. The results demonstrate that engineering nonzero topological charge through the number, shape, size and position of internal holes within dielectric dopants enables flexible manipulation of the internal magnetic field distributions, thereby providing precisely control over the effective permeability, as well as the resonance frequency and spectral linewidth of the transmission spectrum. The proposed multi-dimensional photonic doping strategy, integrating topological-charge engineering with geometric design, substantially enriches the available degrees of freedom for dispersion engineering and provides a versatile platform for advanced functional photonic devices.

We report a $\gamma$-ray excess toward the radio-quiet narrow-line Seyfert 1 galaxy 1H 1934-063 using data collected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope and taking into account the LAT 16-year Source List (FL16Y). During the flare interval, the excess is detected in the 1–500 GeV band at a significance of $\sim 5.2\sigma$ (TS = 27.12), with a photon flux of $(4.94\pm2.33)\times10^{-10}$ ph cm$^{-2}$ s$^{-1}$ and a hard photon index of $\Gamma=1.50\pm0.25$. The best-fit $\gamma$-ray position is consistent with the radio position of 1H 1934-063, while the nearby source FL16Y J1936.9-0552 is not significantly detected during the same interval. In the absence of contemporaneous multiwavelength data, the broadband interpretation cannot be tightly constrained. A compact nonthermal component can produce the hard GeV emission, but the present data do not allow a unique physical interpretation. The excess therefore provides an interesting case for probing high-energy activity in radio-quiet NLS1 galaxies, although the underlying physical mechanism remains uncertain.

We introduce approximate expressions for the thermodynamics of the two-dimensional Ising model in an external magnetic field. The external field breaks the system's symmetry, which complicates the exact calculation of the free energy. To address this, we write the model in its quaternion representation to apply a small angle approximation with respect to a reference frame. The approximation simplifies the transfer matrix to a centrosymmetric matrix for which the largest eigenvalue is known and depends on the external field strength. We therefore write an approximate expression for the system's free energy and derive the magnetization, susceptibility, internal energy, and specific heat. These results are compared with numerical simulations performed with the BKL algorithm. We find that the approximate expressions and numerical simulations agree in regions where the approximation is valid.

We present a uniform IRAM-30\,m survey analysis of four oxygen-bearing complex organic molecules (COMs), methanol (CH$_3$OH), acetaldehyde (CH$_3$CHO), methyl formate (CH$_3$OCHO), and dimethyl ether (CH$_3$OCH$_3$), toward 50 high-mass star-forming regions (HMSFRs) associated with 6.7\,GHz methanol masers. Column densities were derived through a homogeneous rotation-diagram approach, with CH$_3$CN used as a proxy excitation-temperature reference when needed. In CH$_3$OH-normalized abundance-ratio space, CH$_3$OCHO/CH$_3$OH and CH$_3$OCH$_3$/CH$_3$OH show the strongest pairwise correlation, whereas the correlations involving CH$_3$CHO are weaker. No clear monotonic trends are found with Galactocentric distance or beam-averaged H$_2$ column density. Comparison with previous observations places the CH$_3$OCHO–CH$_3$OCH$_3$ behavior within the range of earlier abundance-ratio measurements, while CH$_3$CHO shows larger inter-study variation. A representative warm-up chemical model is used only for qualitative comparison with the observed abundance ranges, which are most closely matched during the decline from the post-desorption abundance peaks in the model. These results provide homogeneous beam-averaged abundance-ratio constraints for common O-bearing COMs in high-mass star-forming regions and show that their source-to-source behavior is molecule-dependent rather than fully described by a single common abundance pattern.

Mapping the dispersion of polaritons, hybrid quasiparticles arising from light-matter coupling, can provide key insights into the material dielectric response, coupling strength, and energy transfer pathways with other excitations. In this work, we present THz pump-Raman probe (TP-RP) as a versatile method for mapping the polariton dispersion in polar non-centrosymmetric materials, demonstrated here for the case of phonon-polaritons in LiNbO$_3$. By resonantly driving polaritonic modes with a broadband THz pump and probing them with a tunable NIR Raman pulse, TP-RP allows for the extraction of the momentum-dependence of both their frequency and damping rate with high accuracy. The spectral features observed in the pump-probe signal, including the polaritonic response as well as pulse artifacts, are reproduced within a many-body theoretical approach. Applying the technique to study the E(TO$_1$) phonon of LiNbO$_3$ enables the combined analysis of theory and experiments to uncover a nontrivial frequency dependence of the phonon intrinsic damping rate, revealing possible anharmonic couplings to other modes.