Modern Physics Letters B

This paper addresses the problem of steady two-dimensional magnetohydrodynamics (MHD) migration of dusty fluid across a stretching sheet with the inclusion of Darcy–Forchheimer porosity and Brownian dispersion. The most significant aspect of the ongoing problem is elaborating the entire context with dusty and fluid phases. The governing partial differential equations (PDEs) are transmuted into non-dimensional ordinary differential equations (ODEs) by implementing similarity transformations. The MATLAB script has used the bvp4c strategy to accumulate a visualization of the computational observations. Also, this study illustrates an assessment of the effects of significant parameters on non-Newtonian fluids and fluids with a dusty phase. It is observed that the thermal boundary layer is enhanced with the increasing strength of the mass concentration of dusty granules (${\mathrm{\Gamma }}_{\nu }$) and Eckert number (Ec) for both scenarios, while in the case of fluid interaction temperature parameter (${\beta }_t$) the scenario is opposite for dusty and fluid phases. Moreover, the heat transfer rate intensifies with the increasing effect of thermal radiation, and magnetic field. The significant variations in the various physical quantities are represented through tabular and graphs.

The nonlinear coupled Schrödinger equation in fiber Bragg gratings is studied in this paper. The existence of soliton solutions and periodic solutions are proved by qualitative analysis, and exact solutions are given, as well as the parameter condition of each solution is described. Then the modulation instability (MI) analysis is carried out and the linear stability criterion is given. In particular, external perturbation terms are introduced to prove that the equation exists chaotic behaviors.

Nanofluids with peristaltic flows are being studied in depth because they can be used in so many different ways, such as to diagnose and treat diseases. In this paper, the peristaltic flow of a nanofluid with viscosity and electric conductivity that change with temperature is used. There are different base fluids and nanoparticles that are being thought about. First, the governing equations are modeled, and then they are made easier to understand by assuming that the wavelength is long and the Reynolds number is small. To make a dimensionless differential system, the right dimensionless numbers are added. Mathematica’s built-on function NDSolve is used to figure out the numerical solution of the resulting system. To figure out how fast heat moves, researchers compare different combinations of base fluids and nanoparticles.

Quantum information protocols are often designed in the ideal situation with no decoherence. However, in real setup, these protocols are subject to the decoherence and thus reducing fidelity of the measurement outcome. In this work, we analyze the effect of state-dependent bath on the quantum correlations and the fidelity of a single qubit teleportation. We model our system-bath interaction as qubits interacting with a common bath of bosons, and the state dependence of the bath is generated through a projective measurement on the joint state in thermal equilibrium. The analytic expressions for the time evolution of entanglement, discord and average fidelity of quantum teleportation are calculated. It is shown that due to the presence of initial system-bath correlations, the system maintains quantum correlations for long times. Furthermore, due to the presence of finite long-time entanglement of the quantum channel, the average fidelity is shown to be higher than its classical value.

The discrete Ablowitz–Ladik (AL) equation is the discrete version of nonlinear Schrödinger equation, which may have potential physical applications in nonlinear optics, polaron motion and anharmonic lattice dynamics. In this paper, a discrete reverse-time nonlocal coupled AL equation is first proposed and studied. First of all, we correspond this new discrete reverse-time nonlocal equation to continuous nonlocal coupled equation by use of the continuous limit technique. Second, we build the generalized $(k,N-k)$-fold Darboux transformation for this new discrete equation. As an application, we obtain some novel position controllable nonlocal singular rogue wave (RW) and period wave solutions on constant seed backgrounds, whose structures and positions are controlled by some special parameters. Moreover, we also study dynamical behaviors of some RW solutions via numerical simulations and large asymptotic analysis. These new results and phenomena may be helpful to comprehend some physical phenomena.

This study introduces a single-layer patterned graphene metamaterial, composed of a graphene ring (GR), two parallel graphene strips (TPGSs), two vertical graphene strips (TVGSs), and a graphene block (GB), which achieves triple plasmon-induced transparency (TPIT) in the terahertz (THz) frequency range using coupled mode theory (CMT) and the finite-difference time-domain (FDTD) technique. Moreover, a synchronized electro-optical switch with four modulation modes is implemented by dynamically adjusting graphene’s Fermi level, exhibiting modulation degrees of amplitude (MDA) of 88.3%, 94.7%, 86.9%, and 89.0% at 1.69THz, 3.14THz, 3.95THz, and 4.67THz, respectively. In addition, the modes excited by TPGSs and TVGSs interconvert due to the proposed structure’s symmetry, accounting for the polarization insensitivity of TPIT. The enhanced MDA and polarization insensitivity of the electro-optical switch presented in this study significantly surpass those of comparable electro-optical switches. As a result, the polarization insensitivity of multiple optical switches to incident light fields offers a promising approach for designing optoelectronic devices.

GaInAsSb has an important application value in the field of infrared photoelectricity. In this paper, the optical properties of Ga${}_{0.84}$In${}_{0.16}$As${}_{0.14}$Sb${}_{0.86}$ nanopillar arrays with different shapes are studied by using the finite-difference time-domain (FDTD) method. The simulation results show that the peaks of all structures occur at 950nm to 1100 nm bands and peak up to 97%. Among them, the period and height of the nanopillars and the inclination angle of the incident light will significantly affect the size of the absorption peak of the nanopillars, but not the peak position. However, with the increase of the diameter, the absorption peak of the nanoparticles showed a trend of increasing first and then decreasing, and the peak position of the absorption peak showed a significant redshift. In addition, for the triangular prism structure, its absorption rate in the array structure with high duty cycle is higher than 90%, which provides an important reference for the preparation of high-density integrated infrared optical detector.

This paper presents a low dropout bandgap voltage reference circuit that combines high output voltage accuracy and low temperature-coefficient in a wide temperature range. The low temperature-coefficient is achieved by an advanced high-order curvature compensation technique, which is implemented by a novel exponential piecewise compensation term in a high-temperature range. A supply noise self-regulation technique is proposed to realize an excellent power supply rejection ratio (PSRR) without using any amplifiers in this paper. The proposed high-accuracy voltage reference is designed in a 2$\mu$m bipolar process. The circuit generates a reference voltage of 3.3V and can operate under a minimum supply voltage of 3.8V, while consuming 44.8$\mu$A. The output voltage accuracy is ± 0.15%. The PSRR at 10Hz and 1MHz is $-64$dB and $-78$dB, respectively. The line regulation is 2.45ppm/V in a supply voltage range from 3.8V to 20V. The average temperature coefficient is 11.9ppm/^∘C in a temperature range from $-55^{\circ }$C to +125^∘C.

In this work, reduced graphene oxide (rGO) is generated by an environmentally friendly electrochemical technique using an aqueous solution of 2.5M nitric acid (HNO₃), followed by thermal degradation at a temperature of 750^∘C. To facilitate the exfoliation process, the electrolytic cell was equipped with a continuous supply of 54V DC. The microstructure of the rGO sheet has been analyzed using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The obtained results show that rGO sheets are irregularly stacked together, have a fractured surface, and porous structure. TGA analysis depicts that the total estimated weight loss was observed to be 40% because of the removal of the oxygen functionalities and volatile gases. X-Ray diffraction (XRD) analysis was used to analyze the phase purity, crystalline nature, interatomic distance as well as crystallite size of the rGO sheet. In the Raman study, the value $I_D∕I_G=0.462$, which compares the peak intensity of the D band to intensity of the G band, provides evidence that the structural component associated with the rGO is present.

In this paper, we theoretically investigated the effect of the polycrystalline structure of metal samples on the magnitude of the spin Hall effect. The equation for the dynamics of the averaged over the crystallite momentum of the collectivized conduction electron in the crystalline field of a homogeneous and isotropic polycrystalline metal is obtained. Averaging the obtained equation over all randomly oriented crystallites resulted in an expression for the electric field of the spin Hall effect. It significantly depends on the form of the single-electron atomic radial wave function and on the Hall coefficient. The coefficients of the spin Hall effect for some metals of 3rd–6th periods are calculated. It is shown that the results for nonmagnetic d- and f-metals within the measurement error are consistent with the experimental data. The best match is observed for Pt, $\alpha$-W, $\beta$-W, Pd, Nb, Ag, Mo, Cu and Al. A discrepancy of less than 20% was obtained for Au, Ti, Mn. For the considered rare-earth metals (Lu, Ho, Dy, Gd) only for paramagnetic Lu the correspondence of calculation results and experimental data is obtained. For Ho, Dy, and Gd, which exhibit ferromagnetic and antiferromagnetic states at low temperatures, the discrepancy is more than 35%. Based on the obtained results, the limitations of the developed approach are formulated.

The aim of this research paper is to analytically investigate graphene oxide blood base nanofluid with the impact of dynamic viscosity and viscous dissipation. The increased thermal conductivity of nanofluids over regular fluids motivates this research. The basic flow equations are used to model the flow problem in nonlinear partial differential equations (NLPDEs). The dimensionless parameters, classical lie group, and thermo-physical properties are applied to transform the developed NLPDEs into dimensionless ordinary differential equations (ODEs). The resultant ODEs are resolved using the homotopy analysis method (HAM), and graphical and tabular interpretations are used to note the effects of contributing parameters including magnetic parameter, dynamic viscosity, nanoparticle volume friction, Eckert number, and Prandtl number on the velocity profile and temperature distribution. From the obtained results, we see that the velocity profile is decreasing by increasing magnetic parameter, dynamic viscosity, nanoparticle volume friction, and the temperature profile is increasing by increasing dynamic viscosity and Eckert number. The tabular descriptions of convergence of the presented fluid flow are also provided.

To explore the strong coupling between the combined plasmonic mode supported by the metal nanoparticle and the anapole mode of the dielectric nanoparticle, a hybrid metal–dielectric nanoparticle consisting of the combination of silicon and silica together with the gold dimer is designed and analyzed by the finite element method (FEM). Theoretical simulation reveals that the enhanced electric field enhancement reaches 640 and unidirectional scattering with almost zero backscattering at multiple wavelengths is achieved in the far-field region. Moreover, the calculated Purcell factor of 12,193 and sensitivity of 610nm/RIU of the composite nanoparticle are much higher than those of the single-metal or dielectric nanoparticles. In the end, the impact of different structural parameters on the sensitivity, figure of merit and quality factor is analyzed and described, and the maximum sensitivity, Figure of merit and quality factor are found to be 2360nm/RIU, 18.4 RIU${}^{-1}$ and 19.8 RIU${}^{-1}$. The results reveal a new strategy to develop devices for surface-enhancement Raman scattering (SERS), quantum emitters, and sensors.