Optical properties of Al _x Ga_1−x As/GaAs Woods–Saxon quantum well in the presence of hydrostatic pressure and applied electric field

Abstract

The third harmonic generation (THG), linear and nonlinear optical absorption coefficients (OACs), and refractive index changes (RICs) are investigated in a Woods-Saxon quantum well (QW) modulated by the hydrostatic pressure and applied electric field. The effect of non-uniform aluminum doping(position-dependent effective mass (PDEM)) on the mass of the system is discussed, and further to explore the influence of PDEM on the nonlinear THG, OACs, and RICs of the Woods-Saxon QW. These nonlinear optical properties above are obtained using the compact-density matrix formalism. The electron states in a Woods-Saxon QW under the constant effective mass(CEM) and PDEM are calculated by solving Schrödinger equation via the finite difference technique. The contributions from competing effects of the hydrostatic pressure and applied electric field to the nonlinear optical properties with CEM and PDEM are reported, as well as the comparison with each other. The observations reveal that the regulation of external fields and the influence of PDEM play an important role in the photoelectric properties of QW.

Electronic and nonlinear optical absorption of an off-center hydrogenic donor impurity in GaAs/GaAlAs hexagonal quantum dot under electric field

“…The numerical calculations for an off-center hydrogenic impurity a Al 0.3 Ga 0.7 As/GaAs hexagonal QD with a modulated applied electric field F are performed using the following materials parameters [19][20][21]:…”