arXiv subjects

El Bouâzzaoui Choubabi

Publications and source records attributed to El Bouâzzaoui Choubabi.

13 recordsLinked to original sources

arXiv2023

Thermal quantum coherence of two-qutrit Heisenberg XXZ model with Herring-Flicker coupling and Dzyaloshinskii-Moriya interaction under magnetic field

In this study, we use the concept of $l_1$-norm coherence to characterize the entanglement of a two--qutrit Heisenberg XXZ model for subject to a uniform magnetic field and z--axis Dzyaloshinskii--Moriya interaction with Herring-Flicker coupling. We show the temperature, magnetic field, DM interaction, and distance of Herring-Flicker coupling all can control the entanglement. However, the state system becomes less entangled at high temperatures or strong magnetic fields and vice versa. Our findings also suggest that entanglement rises when the z--axis DM interaction increases. Moreover, by setting the strengths coupling of the spin, we quickly recover the isotropic XY and XXX Heisenberg models. Finally, Herring-Flicker coupling affects the degree of entanglement. In fact, when Herring-Flicker coupling and temperature are at small values, the degree of entanglement is at its highest. Still, when Herring-Flicker coupling is at substantial values, the degree of entanglement tends to stabilize.

quant-ph↗

arXiv2022

Quantum teleportation via a two-qubit Heisenberg XXX chain with x-component of Dzyaloshinskii-Moriya interaction

In this paper, we investigate the thermal entanglement and teleportation of a thermally mixed entangled via a two-qubit Heisenberg XXX chain with the x-component $D_x$ of the Dzyaloshinskii-Moriya interaction. Our findings suggest that temperature $T$, spin coupling constant J, and the x-components $D_x$ may influence entanglement of the output states and, consequently, the possibilities of teleportation protocols. Furthermore, these results indicate that the entanglement of the output states requires a low-temperature regime, weak Dzyaloshinskii-Moriya interaction, or an antiferromagnetic chain. Finally, the channel becomes entangled, making the teleportation protocol conceivable and feasible.

quant-ph↗

arXiv2022

Entanglement in a two-qubit Heisenberg XXX chain with x-components of Dzyaloshinskii-Moriya and Kaplan-Shekhtman-Entin-Wohlman-Aharony interactions

This article explores the concurrence, including entanglement, in a two-qubit Heisenberg XXX chain with Dzyaloshinskii-Moriya and Kaplan-Shekhtman-Entin-Wohlman-Aharony interactions. The concurrence expression was developed using the physical variables connected with the chosen system. Our results indicate that temperature, the spin coupling constant $J$, the x-components $D_x$, and $Γ_x$ may all play a role in determining the degree of intricacy between states. Additionally, these findings imply that the separability of states is possible for high-temperature domains or ferromagnetic chains. In contrast, the entanglement of states may be achieved by using high values for the x-components $D_x$ or $Γ_x$ parameters or by using an antiferromagnetic chain.

quant-ph↗

arXiv2022

Electron flow in Monolayer Molybdenum Disulfide Quantum Dot with Magnetic Flux

We study the Dirac electron scattering problem on a potential barrier in a circular quantum dot of Monolayer Molybdenum Disulfide quantum dot MoS2 subjected to magnetic flux. By solving Dirac's equation, we formulate analytical expressions for the eigenstates, scattering coefficients, scattering efficiency, and the reflected current's radial component. We show that the scattering coefficients, the scattering efficiency, and the radial component of the reflected current depend explicitly on the magnetic flux. The magnetic flux may cause a slight shift in the oscillation position of the scattering coefficients. For scattering efficiency, magnetic flux may also lead to a slight shift in their oscillation position and an increase in amplitude when the magnetic flux decreases.

cond-mat.mes-hall↗

arXiv2021

Local quantum uncertainty of two gravitational cat states in inhomogeneous magnetic field

This paper investigates the local quantum correlations (LQU), including entanglement, of two gravitational cat states subjected to an inhomogeneous magnetic field. We derived the LQU expression from the physical quantities associated with the selected system. Our findings suggest that temperature, magnetic field, and magnetic field inhomogeneity may all play a role in determining the degree of intricacy between the gravcats to some extent. Furthermore, these conclusions suggest that the thermal LQU captures a stronger quantum correlation than the entanglement. Especially true for low external magnetic field levels combined with low field inhomogeneity or high-temperature domains. Besides, we obtained the states' separability for large values of field inhomogeneity. Moreover, the correlation of the states obtained is maximal for small magnetic field values at low temperatures. Finally, we note that the state's systems become non-entangled and separable when the gap between the fundamental level and the first excited level becomes large.

quant-ph↗

arXiv2021

The correlation function of a two-dimensional electron gas with anharmonic potential and Rashba coupling

In this paper, we study a two-dimensional gas of electrons with Rashba spin-orbit coupling with anharmonic potential. The splitting of the Hamiltonian in two parts can be recovering the Jaynes-Cummings model, which describes a system with two states. The dynamics of the rising Pauli operator and the creation operators are studied. Finally, we examined the behavior of the correlation function of emission and absorption photons for the strong and weak coupling.

cond-mat.mes-hall↗

arXiv2021

Energy levels of monolayer -- AA-stacked bilayer graphene quantum dots

This work investigates the electronic properties of the energy spectrum of a hybrid system composed of (i) a circular quantum dot of monolayer graphene surrounded by an infinite sheet of AA-stacked bilayer graphene and (ii) a circular quantum dot of AA-stacked graphene bilayer surrounded by infinite monolayer graphene. We establish analytical findings for the related energy levels and wave functions using the continuum model and the zigzag boundary conditions at the graphene monolayer-bilayer interface. We investigate the effects of perpendicular magnetic, dot radius, and electrical fields on the two types of hybrid system quantum dots. We compare our results to previously published work and explore the potential uses of such a hybrid system quantum dot.

cond-mat.mes-hall↗

arXiv2021

Scattering in Monolayer Molybdenum Disulfide Quantum Dot

We investigate the propagation of electrons in a circular quantum dot of monolayer Molybdenium disulfide MoS_2, subjected to an electric potential. Using the continuum model, we present analytical expressions for the eigenstates, scattering coefficients, scattering efficiency, and radial component of the reflected current and electron density. We identify two scattering regimes as a function of physical parameters such as incident electronic energy, potential barrier, and quantum dot radius. For the incident electron low energy, we show that there is an appearance of scattering resonances. Also, we note that the Far-field scattered current has distinct preferred scattering directions.

cond-mat.mes-hall↗

arXiv2019

Electronic Structure of Graphene with two Strains and Double Barrier

We study the electronic structure of Dirac fermions scattered by double barrier potential in graphene under strain effect. We show that traction and compression strains can be used to generate fermion beam collimation, 1D channels, surface states and confinement. The corresponding transmission probability and conductance at zero temperature are calculated and their numerical implementations taking into account different configurations of physical parameters enabled us to analyze some features of the system.

cond-mat.mes-hall↗

arXiv2019

Transmission in Graphene through Time-oscillating Linear Barrier

Transmission probabilities of Dirac fermions in graphene under linear barrier potential oscillating in time are investigated. Solving Dirac equation we end up with the solutions of the energy spectrum depending on several modes coming from the oscillations. These will be used to obtain a transfer matrix that allows to determine transmission amplitudes of all modes. Due to numerical difficulties in truncating the resulting coupled channel equations, we limit ourselves to low quantum channels, i.e. $l = 0, \pm1$, and study the three corresponding transmission probabilities.

cond-mat.mes-hall↗

arXiv2018

Transport Properties in Graphene Superlattices

Using Chebyshev polynomials, we study the electronic transport properties of massless Dirac fermions in symmetrical graphene superlattice composed of three regions. Matching wavefunctions and using transfer matrix method, we explicitly determine transmission probability as well as the conductance and Fano factor. At vertical Dirac points, we numerically find that the transmission probability shows transmission gaps, conductance has minimums and Fano factor has maximums.

cond-mat.mes-hall↗

arXiv2017

Band Structures of Symmetrical Graphene Superlattice with Cells of three Regions

We study the electronic band structures of massless Dirac fermions in symmetrical graphene superlattice with cells of three regions. Using the transfer matrix method, we explicitly determine the dispersion relation in terms of different physical parameters. We numerically analyze such relation and show that there exist three zones: bound, unbound and forbidden states. In the central zone of the band structures, we determine and enumerate the vertical Dirac points, opening gaps and additional Dirac points. Finally, we inspect the potential effect on minibands, the anisotropy of group velocity and the energy bands contours near Dirac points. We also discuss the evolution of gap edges and cutoff region near the vertical Dirac points.

cond-mat.mes-hall↗

arXiv2015

Transmissions in Graphene through Double Barriers and Periodic Potential

Transmission of Dirac fermions through a chip of graphene under the effect of magnetic field and a time vibrating double barrier with frequency $w$ is investigated. Quantum interference within the oscillating barrier has an important effect on quasi-particles tunneling. A combination of both a time dependent potential and a magnetic field generate physical states whose energy is double quantified by the pair of integers $(n, l)$ with high degeneracy. The large number of modes that exist in the energy spectrum presents a colossal difficulty in numerical computations. Thus we were obliged to make a truncation and limit ourselves to the central $(n = 0)$ and two adjacent side band ($n=\pm 1$).

cond-mat.mes-hall↗