Theoretical Study of Nonlinear Absorption of a Strong Electromagnetic Wave in Infinite Semi-parabolic plus Semi-inverse Squared Quantum Wells by Using Quantum Kinetic Equation

TL;DR

This paper derives analytical expressions for the nonlinear absorption of strong electromagnetic waves in complex quantum wells, incorporating multi-photon processes and exploring dependencies on various physical parameters through numerical analysis.

Contribution

It provides the first comprehensive theoretical analysis of nonlinear absorption in semi-parabolic plus semi-inverse squared quantum wells using quantum kinetic equations, including multi-photon effects.

Findings

Absorption coefficient depends on photon energy, enabling optical detection of sub-bands.

Theoretical rules for FWHM dependence on temperature and magnetic field.

Results align with previous theoretical and experimental data.

Abstract

General analytic expressions for the total absorption coefficient of strong electromagnetic waves caused by confined electrons in Infinite semi-parabolic plus Semi-inverse Squared Quantum Wells (ISPSISQW) are obtained by using the quantum kinetic equation for electrons in the case of electron-optical phonon scattering. A second-order multi-photon process is included in the result. The dependence of the total absorption coefficient on the intensity $E_0$, the photon energy $\hbar \Omega$ of an SEMW, and the temperature T for a specific GaAs/GaAsAl ISPPSISQW is achieved by using a numerical method. The computational results demonstrate that the total absorption coefficient's dependence on photon energy can be utilized for optically detecting the electric sub-bands in an ISPPSISQW. Besides, we also give theoretical rules on the dependence of the Full Width at Half Maximum on important external parameters such as temperature and perpendicular magnetic field. Furthermore, the obtained results are consistent with prior theoretical and experimental findings.