Modern Physics Letters B

In this paper, a (2+1)-dimensional generalized Calogero-Bogoyavlenskii-Konopelchenko-Schiff system in a fluid or plasma is investigated. Via the Hirota method and symbolic computation, we work out some two-resonance Y-type soliton solutions as well as some hybrid solutions composed of the two-resonance Y-type solitons and solitons/breathers. Graphically, we display some two-resonance Y-type solitons. We present the interactions between the two-resonance Y-type soliton and one soliton, among the two-resonance Y-type soliton and two solitons, between the two-resonance Y-type soliton and first-order breather as well as among the two-resonance Y-type soliton and second-order breathers.

The major objective of this research is to create a novel mathematical model for the flow of an electro-osmotic boundary layer in a micropolar Williamson nanofluid. This development is achieved by considering the influence of electro-osmotic force on an incompressible micropolar Williamson nanofluid through a Darcian flow (Darcy model) when combined with a binary chemical reaction and the energy of activation over a linearly stretching sheet. The constituent parts of the energy equation include heat radiation, thermal and mass transport, along with joule-based heating and dissipation of viscous fluids. The problem is computationally analyzed using an equation set of nonlinear partial differential equations (PDEs), which are then similarly converted into a system of ordinary differentiation equations (ODEs). The obtained ODEs system is solved numerically using the built-in command (Parametric ND Solve) via MATHEMATICA software. A series of figures are used to demonstrate numerically and graphically the influence of physical characteristics on the fluid behavior. The behavior of flow is obtained by studying the streamlines around the plate in contour and three-dimensional form. In the case of non-Newtonian fluid, the results indicated that the boundary layer velocity is slower compared with the Newtonian fluid case. It is also mentioned that the graphic representation of the results shows that increasing the radiation parameter enhances thermal distribution, which means that the rate of heat transfer improved. The main findings revealed that the upward trend in the Williamson number diminishes the nanofluid flow while enhancing the skin friction coefficient. Also, it is discovered that as $m_e$ rises, the fluid’s velocity distributions in the boundary layer rise. Consequently, this type of research’s significance stems from its potential uses in biomedical engineering since it could be used to dewater liquids and solids from infected human tissues.

The deterioration of precision caused by quantum decoherence in dissipative environments is a longstanding problem in the development of distributed quantum metrology. Therefore, it is significant to effectively overcome the entanglement-distribution loss and channel noise of dissipative environments and improve the measurement-sensitivity. Here, we introduce noiseless linear amplifier (NLA) based on photon catalysis into distributed phase estimation to mitigate the loss and noise. Through utilizing a series of reduction and equivalence relations to simplify the problem of distributed phase estimation to a single-parameter estimation situation, our results show that Photon catalysis (PC)-NLAs can effectively mitigate the loss and noise of dissipative environments, and greatly improve the measurement-sensitivity. More interestingly, we find that adding thermal photons of environment has positive contributions on the measurement-sensitivity under certain circumstances. Our scheme should prove valuable for the global wide-area quantum sensor network.

In this study, DSC and infrared spectra of nano ZrC particles were recorded in the 25–$950^{\circ }$C temperature and 400–4000cm${}^{-1}$ spatial frequency range, respectively. All experiments were compared before and after gamma irradiation (5, 15, 50 and 150 Mrad doses). The causes of infrared peaks characterizing C-OH groups and C-O oscillations were investigated in ZrC nanoparticles. Gamma radiation-induced changes are described in the peaks of the IR spectra. The explanation of existing bonds in IR spectra is given by DSC and TG curves. The act of OH groups adsorbed on the surface of nanoparticles and other processes is investigated as a function of temperature with DSC and TG curves.

Self-focusing of a laser beam is one of the major consequences of nonlinear interaction of laser with plasma. In this paper, self-focusing of skew cosh Gaussian (skew-ChG) laser beam is studied in anisotropic, collisional plasma where in externally exponentially decreasing magnetic field is applied. Skewness parameters in the field profile of skew-ChG laser beam eventually determine intensity profile of the beam. The symmetry in skewness parameter in two transverse directions simplifies the calculations considerably. Second order, nonlinear, ordinary, coupled differential equations for Beam Width Parameters (BWP) are obtained using Akhmanovs approach under Wentzel–Kramers–Brillouin (WKB) and paraxial approximations which are solved numerically. For given amplitude of applied magnetic field, attenuated oscillatory self-focusing is observed with respect to change in attenuation coefficient.

In this paper, La${}_{1-x}$Ca_xFeO₃ ($x=0$, 0.1, 0.2, 0.3, 0.4, 0.5) perovskite samples were synthesized by sol–gel method. X-ray diffraction (XRD), transmission electron microscopy (TEM) and Mössbauer were used for measuring. XRD measurement shows that the unit cell volume of LaFeO₃ gradually decreases with increasing Ca content. The morphology of the sample was observed by TEM, and there were significant changes in volume and size of the samples with different calcium contents. Mössbauer spectrum study found that with the gradual increase of Ca content, Fe${}^{3.5+}$ and Fe${}^{4+}$ were formed in the sample. The study in this paper will provide a reference for future research on the effect of different calcium contents on the electronic structure of lanthanide ferrite.

In this paper, a finite spin system corresponding to magnetic molecules with the wheel geometry is discussed in the Ising-like limit of the Heisenberg Hamiltonian. We put stress on the ground state degeneration, which is determined with the use of some discrete mathematics methods, especially investigating some integer sequences, including the famous Fibonacci one.

In this paper, the structural, electrical and optical effects of WS₂ doped with silicon atoms after torsional deformation are investigated using first-principles calculations. First-principles calculations for metal disulfide-WS₂. The doping of Si atoms gives WS₂ a tunable band gap, and the surface state is successfully transformed from a 2.0eV band gap to a quasi-metal with a 0.254eV band gap, and the change of the doped Si atoms causes a redshift in the absorption peak and a blueshift in the reflection peak. The band gap of WS₂ can be effectively adjusted by torsional deformation on the basis of Si-doped atoms in the range 0.254–0.052eV. Calculations of optical properties show that Si-doped WS₂ with a torsion angle of $10^{\circ }$ has the lowest light absorption peak and Si-doped WS₂ with a torsion angle of $8^{\circ }$ has the lowest light reflection peak. This paper opens up new possibilities for designing materials on demand.

Steering is a type of nonseparable quantum correlation, where its inherent asymmetric feature makes it distinct from Bell nonlocality and entanglement. In this paper, we investigate quantum steering in a two-mode Gaussian state ${\widehat{\varrho }}_{c_1{c}_2}$ coupled to a two-mode vacuum reservoir. The mode $c_1$ ($c_2$) is emitted during the first (second) transition of a nondegenerate three-level cascade laser. By means of the master equation of the state ${\widehat{\varrho }}_{c_1{c}_2}$, we derive the analytical expression of the steady-state covariance matrix of the modes $c_1$ and $c_2$. Using realistic experimental parameters, we show that the state ${\widehat{\varrho }}_{c_1{c}_2}$ can exhibit asymmetric steering. Furthermore, by an appropriate choice of the physical parameters of the state ${\widehat{\varrho }}_{c_1{c}_2}$, we show that one-way steering can be achieved. Essentially, we demonstrate that one-way steering can, in general, occur only from $c_1\to c_2$. Besides, we perform a comparative study between the steering of the two laser modes and their Gaussian Rényi-2 entanglement. As a result, we found that the entanglement and steering behave similarly in the same circumstances, i.e. both of them decay under dissipation effect; moreover, they can be well enhanced by inducing more and more quantum coherence in the state ${\widehat{\varrho }}_{c_1{c}_2}$. In particular, we found that the steering remains always less than the Gaussian Rényi-2 entanglement.

Based on the magnetic dipole theory and the elastic mechanical plane strain method, this paper establishes a multi-chain model of ferromagnetic particle inclusions–superconducting matrix and investigates the effects of the distribution form of ferromagnetic particle inclusions and elastic parameters on the effective magnetostriction of superconductors. A dimensionless parameter is introduced to describe the spatial distribution form of ferromagnetic particles in the matrix, and the calculation is carried out using the elastic mechanical plane strain method. The change of the effective magnetostriction following the elastic parameter is given for three kinds of distribution forms: single-chain, planar–laminar, and spatial three-dimensional multi-chain, respectively. The results show that the distribution of ferromagnetic particle inclusions and the change of elastic parameters have a notable influence on the displacement and magnetostrictive distribution of superconductors.

The coupled nonlinear Schrödinger (CNLS) system is often used to describe physical problems such as wave propagation in a birefringent optical fiber. Under investigation in this paper is the nonlocal ${𝒫}{𝒯}$-symmetric reverse-space type of CNLS system, through constructing two types of Darboux transformation (DT), we will derive a new series of nonlocal analytic solutions: (1) Single-periodic and double-periodic solutions; (2) Four different combinations about dark and anti-dark solitons, as well as the bright and dark breathers on a periodic background. Moreover, the fundamental properties and dynamical behaviors of those solutions will be discussed.

The antiferromagnetic (AFM) spin-3/2 Heisenberg model is explored by using a mean-field approach (MFA) with the inclusion of spin operators for a square lattice. The considered Hamiltonian consists of the bilinear exchange interaction $J_z$ and Dzyaloshinskii–Moriya interaction (DMI) ${\mathrm{\Delta }}_m$ parameters between the nearest-neighbor (NN) spins along the z- and y-axes and external magnetic field components $H_x$ and $H_z$ acting along the x- and z-axes, respectively. After obtaining the mathematical formulation of the magnetization components along the x- and z-directions in the MFA, their thermal changes are inspected to obtain the phase diagrams on the (${\mathrm{\Delta }}_m$, T) and (H, T) planes for the given values of $H=H_x=H_z$ and ${\mathrm{\Delta }}_m$, respectively, with $J_z=-1$ which leads to AFM interactions. It is found that the model not only presents the AFM and ferromagnetic (FM) phases but also the random (R) phase regions created by the existence of ${\mathrm{\Delta }}_m$ interaction. These three phases are observed to coexist for the appropriate values of given system parameters. The phase lines exhibit reentrant behavior when only the FM and R phases are present.