Volume 80, Issue 11

Two fiber optic direct current (DC) electric field sensors are proposed based on electrically tunable liquid crystal (LC) is proposed. The two sensors have the transmissive and reflective structure, respectively. The multimode fiber is connected to the LC device, enabling the measurement of the transmittance and reflective interferometric spectra. The variation of the applied electric field can cause the change in the effective refractive index of the LC, and the intensity or wavelength of light passing through the LC device can be continuously tuned when the applied electric field exceeds a threshold value. In the electric field range of 280–520 V/mm, with the increase of the electric field intensity, the transmittance of the sensor decreases, the linear sensitivity is 0.40549 %/(V/mm) with the detection limit (LOD) of 0.20028 V/mm. For the sensor with the reflective structure, the blue shift occurs with the increase of electric field intensity, and the linear sensitivity of 0.0474 nm/(V/mm) with the LOD of 0.12152 V/mm. In addition, the sensors have the advantages of good repeatability, low cost, high sensitivity, etc., and have potential applications in the electric field sensing and photoelectric switches.

This study offers a comprehensive analysis of a modified (1 + 1)-dimensional longitudinal wave equation (LWE) tailored to explain the nonlinear dynamic structure of a magneto-electro-elastic (MEE) circular rod. The model presents the coupled interactions of electrical and magnetic fields and mechanical interactions by including physical characteristics such as stress-strain and mass density relationships, reflecting deeper insight into the propagation of longitudinal waves in MEE material. To exhibit the symmetry structure of the equation, Lie symmetry analysis approach is used, producing symmetry reductions that reduce the original partial differential equation into ordinary differential systems. Beyond the symmetry system, the dynamics of the model is methodically analyzed through different diagnostic tools, such as multistability analysis, bifurcation diagrams, power spectrum plots, heterogeneous recurrence plots, Lyapunov exponent evolution, and strange attractor representations, capturing rich chaotic dynamics and sensitive dependence on distinct initial conditions. Additionally, we create novel exact solutions of the proposing equation using two advanced symbolic techniques namely, the generalized Ansatz method and the Painlevé–Paul method to derive a wide spectrum of wave profiles, including kink, anti-kink, periodic, W-shaped, and mixed-type solutions. The importance of this work lies in its unified analysis of symmetry, chaos, and soliton theory within a physically motivated structure, inproving our understanding of nonlinear wave propagation in magneto-electro-elastic structures and providing valuable tools for modeling complex materials in applied physics and engineering contexts.

The emergence of synchrony essentially underlies the functionality of many systems across physics, biology and engineering. In all established synchronization phase transitions so far, a stable synchronous state is connected to a stable incoherent state: For continuous transitions, stable synchrony directly connects to stable incoherence at a critical point, whereas for discontinuous transitions, stable synchrony is connected to stable incoherence via an additional unstable branch. Here we present a novel type of transition between synchrony and incoherence where the synchronous state does not connect to the state of incoherence. We uncover such transitions in the complexified Kuramoto model with their variables and coupling strength parameter analytically continued. Deriving a self-consistency equation for a quaternion order parameter that we propose helps to mathematically pin down the mechanisms underlying this transition type. Local numerical analysis suggests that the transition is linked to a Hopf bifurcation destabilizing synchrony, in contrast to branching point bifurcations established for the transition between synchrony and incoherence so far.

Improving the efficiency of electron acceleration in a vacuum presents a significant challenge in sophisticated laser-driven acceleration methodologies. This research examines the combined effects of Hermite-Sinh-Gaussian (HShG) laser beams (laser electric field amplitude, Hermite polynomial mode index, Decentered parameter of Sinh function) and magnetic wigglers (wiggler magnetic field amplitude, wiggler field propagation constant) on electron dynamics to facilitate high-energy acceleration. The distinct intensity and phase distribution of HShG beams alter the trajectory of electrons, facilitating effective energy transfer. The periodic magnetic field of the wiggler enhances resonance conditions, thereby sustaining prolonged interactions between electrons and the laser field. The numerical analysis indicates that the integration of these two mechanisms markedly enhances the relativistic factor ( γ ) of electrons, resulting in greater energy gains. The findings demonstrate that customized laser beam configurations and external magnetic fields can enhance laser-driven acceleration in vacuum, presenting a viable strategy for future compact accelerators. This study offers insights into optimizing acceleration efficiency for high-energy physics applications, free-electron lasers, and advanced radiation sources.

In this paper, we will study the steady-state laminar flow of an electrically conducting fluid under the influence of a magnetic field through a tube with permeable walls. The fluid flow is described by a nonlinear system given by the Navier–Stokes equations taking into account magnetic-induced effects. The main goal is to investigate the effects of the porosity of the tube and the magnetic field on the fluid flow. Using asymptotic analysis with respect to the small parameter representing the ratio between the tube’s thickness and its length, we construct an explicit first-order approximation for the axial and radial velocity of the fluid. The first-order asymptotic approximation takes into account the porosity of the tube as well as the effects of the magnetic field on the fluid flow through the presence of the corresponding nondimensional parameters, and we illustrate this by providing numerical examples.

The lead-cooled fast reactor (LFR), one of the prominent concepts among Generation IV nuclear reactors, operates with a fast neutron spectrum and utilizes molten lead or lead-bismuth eutectic as coolant. Research on Generation IV reactors has recently gained significant momentum due to the increasing need for clean and sustainable energy sources to mitigate the environmental impact of fossil fuels. In this study, alternative coolant candidates for future nuclear reactors have been explored, including mercury, iron, thallium, tin, aluminum, and ferrite. The radiative capture cross-sections [(n, γ) reactions] of selected materials – namely Pb, Hg, Fe, and Sn – were calculated using the TALYS 1.95 nuclear reaction code. Certain materials were evaluated both in their elemental forms and as halide compounds or eutectic alloys. The neutron-induced gamma production (radiative capture) cross-sections were analyzed and compared to assess the viability of these substances as potential coolants. This comparative analysis aims to identify promising candidates that could offer improved neutron economy, thermal properties, and structural compatibility for next-generation fast reactor designs.

The ternary system of equiatomic transition-metal arsenides offers promise for topological superconductors, but their structural stability and mechanical properties remain largely unexplored. By means of the first-principles calculations, the Co 2 P-type orthorhombic structure is predicted to stable ground states of TT ′As ( T = Ti, Zr, or Hf; T ′ = Ru or Os), and the experimentally reported ZrRuAs and HfRuAs with the Fe 2 P-type hexagonal structure only is the high-temperature phases. Although the Fe 2 P-type structure of ideally stoichiometric TiRuAs, TiOsAs, ZrOsAs, and HfOsAs exhibits the thermodynamic and elastic stability, their phonon spectrums always have some imaginary frequencies below 2,500 K, indicating dynamical instability. The calculations on their mechanical properties indicate that these TT ′As compounds are a class of low-compressible and ductile materials. Moreover, they also possess moderately high shear stiffness and hardness. The electronic structures of representative HfRuAs are analyzed to reveal the underlying origin of the intriguing physical properties.

We present a pioneering investigation into the thermodynamic properties of the one-dimensional (1-D) inverted harmonic oscillator confined within a quantum well. Utilizing the linear variational method, we compute the eigen-energy of the confined inverted harmonic oscillator (CIHO) and find good agreement with exact solutions. Our analysis unveils an intriguing phenomenon: the energy of the CIHO can exhibit both positive and negative values due to the interplay between quantum confinement and the inverted harmonic potential. This anomalous behavior directly affects the system’s quantum statistics thermodynamic properties. Our calculation reveals that, for a fixed quantum well width, the average energy, free energy, and entropy all decrease as the inverted harmonic frequency increases. However, the variation of heat capacity ( C V ) with harmonic frequency is remarkably peculiar. Specifically, in the low-temperature region, C V diminishes with increasing harmonic frequency, while the opposite trend occurs at higher temperatures. We also investigate the influence of quantum confinement on the thermodynamic properties of the CIHO. Our results indicate that the thermodynamic properties of the CIHO can be effectively controlled by adjusting both the size of the quantum well and the harmonic frequency. This work can guide the future research on the thermodynamic property of the confined harmonic oscillator and may find applications in various fields, including high-energy physics, condensed state physics, statistical physics, and cold atomic physics.