Based on a coupled resonator array, we theoretically construct and numerically simulate a nonlinear quantum optics platform to dynamically control the Bloch wavevector. By scanning the modulation parameters ( alpha,ky), we reproduce the Hofstadter's butterfly structure in the biphoton energy spectrum and reveal clear correspondences among the eigenenergy spectrum, transmission spectrum, and biphoton joint spectral intensity (JSI). Further research demonstrates that screening the pump wavelength can effectively tailor the JSI profile and the Schmidt number of the quantum state, enabling flexible manipulation of frequency entanglement characteristics. This work provides a theoretical framework for exploring quantum state generation and manipulation in nonlinear topological photonic systems and demonstrates the potential for realizing programmable quantum light sources in integrated quantum photonic circuits.
Abstract In this work, we investigate the optical and thermodynamic properties of an effective hybrid regular black-hole geometry endowed with Lorentz-violating hair and surrounded by a quintessence-like field. The modified metric incorporates a regularizing term associated with Lorentz-symmetry breaking, whose effects are examined through the behavior of the ADM mass, Hawking temperature, Gibbs free energy, and heat capacity. Our analysis reveals significant modifications to the near-horizon structure, thermal stability, and phase-transition patterns, including the emergence of swallow tail-like signatures in the free energy and shifted divergence points in the specific heat. The results show that Lorentz-violating effects, together with the electric charge, string cloud density, and quintessence state parameter, play a decisive role in determining the physical characteristics and thermodynamic phases of the system. These findings provide new insights into black hole phenomenology within extended gravitational frameworks and highlight the interplay between fundamental symmetry breaking and effective matter fields.
Abstract We investigate the existence, stability, and nonlinear dynamics of high-charge vector vortex solitons (VVSs) in a (2+1)D vectorial cubic-quintic complex Ginzburg-Landau model describing multimode laser cavities. The analysis combines a variational approach (VA), radial linear stability theory based on the Routh-Hurwitz criterion, and direct numerical simulations of the full field equations. We demonstrate that vortex-antivortex pairs with opposite topological charges \((+m,-m)\) and \(m \ge 2\) can be stabilized within specific dissipative regimes through the combined action of cubic-quintic nonlinearities, gain-loss balance, and vectorial coupling between polarization components. The VA reveals that the topological charge \(m\) plays an active role in the underlying energy balance: increasing \(m\) leads to broader beam widths and higher total power, while reducing the stationary amplitude and wavefront curvature, thereby reshaping the stability landscape. Linear stability analysis of the variational system further shows that the domain of radially stable fixed points contracts as \(m\) increases, confirming the enhanced sensitivity of high-charge vortices to perturbations at the level of the collective-coordinate dynamics. These variational predictions are fully supported by direct numerical simulations of the full model, which reveal a rich variety of dynamical scenarios, including stable propagation, self-confinement into fundamental solitons, and azimuthal symmetry breaking with fragmentation into pinned intensity peaks. In the latter case, the breakup process is interpreted as a redistribution of orbital angular momentum (OAM) among emerging structures rather than its destruction. Overall, this study provides a comprehensive physical picture of dissipative VVSs in nonlinear laser systems and identifies robust stabilization regimes for high-order topological states. The results, grounded in a Maxwell-Bloch-derived model, suggest realistic conditions for experimental observation and open perspectives for applications in structured light engineering, optical information encoding, and OAM-based photonic devices.
Abstract Place cells in the hippocampus and grid cells in the medial entorhinal cortex jointly support spatial representations, yet how interactions between these populations shape representational changes following environmental deformation remains unclear. We developed a biologically grounded circuit model that integrates boundary vector cells, place cells, and modular grid-cell networks through plastic boundary-to-place, place-to-grid, and grid-to-place projections. During initial exposure to compressed or elongated enclosures, grid cells exhibited module-dependent grid rescaling and boundary-conditioned phase shifts, while place cells showed heterogeneous changes in place-field size and position. Transfer-entropy analysis revealed movement- and boundary-axis-dependent shifts in the directional balance of predictive dependence between place- and grid-cell populations relative to the familiar baseline. During departure, this balance shifted toward grid-to-place and place-to-grid predictive dependence along the deformed and undeformed axes, respectively. With repeated familiarization, different representational features followed distinct, geometry-dependent trajectories rather than uniformly reverting to their familiar-environment configurations. Selective blockade of plasticity in individual pathways revealed distinct effects on familiarization: place-to-grid plasticity supported grid-scale recovery and gains in spatial information, boundary-to-place plasticity modestly promoted grid-scale recovery, and grid-to-place plasticity helped constrain rescaling overshoot. Together, these findings suggest that environmental deformation elicits a multidimensional reorganization of spatial representations, shaped by dynamic place–grid interactions and pathway-specific plasticity, rather than a single uniform transformation.
Abstract Detailed numerical results obtained with state-of-the-art Quantum Monte Carlo (QMC) simulations are presented for the superfluid phase of 4 He at saturated vapor pressure. The aim of this contribution is that of providing reliable, up-to-date estimates for this archetypal superfluid, reflecting the methodological progress that has taken place over the past two decades. We simulate a system comprising 2,048 helium atoms, i.e., an order of magnitude greater in size than those for which results currently regarded as standard references were originally obtained. We offer revised estimates for energetic and structural properties, as well as for the ground state condensate fraction.
