The European Physical Journal D最新文献

The nonlinear dynamics of plasma waves in multi-species magnetized systems is of great importance for understanding energy transport and particle interactions in both astrophysical and laboratory environments. This study investigates heavy ion-acoustic kinetic Alfvén solitary waves (HIAKASWs) in a magnetized plasma composed of inertial thermal heavy ions and non-extensive electron–positron pairs. Using the reductive perturbation method, we derive both the Korteweg–de Vries (K-DV) and modified Korteweg–de Vries (MK-DV) equations, which capture the balance between dispersion and nonlinearity, and analyze their soliton solutions under different plasma conditions. The electron and positron populations are described by Tsallis non-extensive statistics, allowing exploration of deviations from Maxwellian behavior. The analysis reveals that the K-DV equation admits both compressive and rarefactive solitary structures, while the higher-order MK-DV formulation supports only compressive modes. Parametric investigations demonstrate that heavy ion thermal pressure and inertia play a dominant role in shaping wave amplitude and width compared to electron and positron effects. The results highlight the influence of non-extensivity, magnetic field strength, and propagation angle on solitary wave characteristics, with implications for plasma dynamics in astrophysical and laboratory environments.

The plots highlight the effects of (beta ), (gamma ), and heavy ion density on dispersion, nonlinearity, and electrostatic potential of K-DV and MK-DV solitons, relevant to astrophysical and laboratory plasmas.

The paper proposes a chemical model for describing of the thermophysical and transport properties of dense plasmas. In this model, plasma consists of weakly interacting electrons, ions, atoms, molecules and molecular ions, and two- and threefold ionized atoms. Corrections for charge–charge and charge–atom interactions were analyzed. The Debye approximation in the Grand canonical ensemble is used to take into account the charge–charge interaction. We showed that the interaction between charges plays a significant role in the calculation of the plasma properties. The caloric and thermal equations of state and composition of the lead plasma were calculated. The calculation results obtained from the suggested model have demonstrated satisfactory agreement with the experimental data on the equation of state and the electrical resistivity measured recently for a dense plasma of lead.

We study the effects of a parametric frequency converter (PFC) in a two-mode cavity system where one of the cavity modes is coupled with yttrium iron garnet (YIG). The PFC acts as a nonlinear source for enhancing quantum correlations, which strongly depend on the parametric coupling and the associated phase factor. It is fascinating that the perfect transfer of entanglement and steering of various mode pairs can be achieved by adjusting the system’s parameters, such as cavity-magnon coupling, gain, and the phase of the PFC. In addition, the generated entanglements in the present system are more robust against thermal effects, particularly with the inclusion of the PFC, compared to the bare-cavity case. Another intriguing finding is that phonon-cavity one-way steering appears only when magnon-cavity one-way steering completely vanishes. Our protocol for these transferring processes suggests a different approach to the processing and storage of quantum information.

Description We study the enhancement of quantum correlation and perfect transfer of entanglement of indirectly coupled modes via a parametric frequency converter (PFC) in a two-mode magnomechanical system. It is fascinating that the perfect transfer of entanglement and steering of various mode pairs can be achieved by adjusting the system’s parameters, such as cavity-magnon coupling, gain, and the phase of the PFC.

Recently, it was shown that a violation of the no-signaling principle can be obtained by using local (PT)-symmetric evolutions on shared quantum states that are entangled and pure. The violation can be removed by using a (CPT) inner product instead of the traditional one. We show that within the traditional inner product quantum mechanics, local (PT)-symmetric evolutions can lead to violation of the no-signaling principle for separable and even for classically correlated bipartite shared quantum states. For classically correlated states, specially chosen (PT)-symmetric operations from a set of zero volume can also preserve the principle. The classically correlated states used for the violation have the same correlation, when only a single basis is considered for measurements, as the maximally entangled states that were erstwhile used for the same purpose. This, along with the fact that states with no classical correlation cannot be used for violation of no-signaling within (PT)-symmetric evolutions, can potentially lead to the identification of minimal resources necessary for obtaining the violation. The violation obtained here can again be removed by using a (CPT) inner product instead of the traditional one.

Quinones are ubiquitous in the biological media. Here, we present elastic integral, differential and momentum transfer cross sections for low-energy electron scattering from the cis- and trans-conformers of hydroquinone (HQ). These cross sections were computed using the Schwinger multichannel method with pseudopotentials in the static exchange and static exchange plus polarization approximations, up to 12 eV. The main distinction between the two conformers is the presence of strong long-range dipole–electron interactions in cis-HQ, which are absent in trans-HQ due to its nonpolar nature. Three resonances were identified for both conformers: The first two correspond to the lowest degenerate (pi ^*) resonance of benzene, while the third exhibits a mixed shape and core-excited character. Comparison with dissociative electron attachment experiments suggests that fragmentation likely occurs via an indirect (pi ^*/sigma ^*) internal conversion pathway for fragments observed at low impact energies. These results provide new cross-sectional data that may support the modeling of electron-driven processes in biologically relevant environments.

.Electron interactions with cis- and trans- hydroquinone. Elastic cross sections and resonant states are reported.

This study presents a comprehensive theoretical and numerical investigation of the nonlinear optical properties of ZnTe@Ag core–shell nanostructures embedded in dielectric host matrices. Particular emphasis is placed on the effects of geometric configuration (spherical vs. cylindrical), shell thickness, and host matrix permittivity on the local field enhancement factor (LFEF) and optical bistability (OB). Analytical expressions for the internal electric fields are obtained by solving Laplace’s equation within the quasi-static approximation. The model employs a size-dependent Drude dielectric function for the metallic shell, while Kerr-type nonlinearity is introduced in the dielectric core or host medium to account for third-order optical effects. The results show that spherical nanoinclusions consistently yield stronger local field enhancement and wider bistability regions than their cylindrical counterparts, attributable to higher geometric symmetry and more efficient field confinement. The LFEF spectra exhibit two distinct resonance peaks whose positions and magnitudes can be effectively tuned by adjusting the shell thickness and host dielectric constant. Moreover, increasing the host matrix permittivity significantly reduces the OB switching thresholds and broadens the bistability window for both geometries. These findings highlight the critical roles of geometry and dielectric environment in tailoring the nonlinear optical response of core–shell nanocomposites, providing valuable design guidelines for tunable plasmonic devices, all-optical switches, and optical memory elements.

Schematic representation of spherical and cylindrical ZnTe@Ag core -shell nanostructures, emphasizing the influence of geometry and dielectric environment on their nonlinear optical properties