The effects of temperature and pressure on the optical properties of a donor impurity in ðIn; GaÞN=GaN multilayer cylindrical quantum dots
Abstract
This paper examines the variation of the linear, third-order nonlinear and total intersubband
optical absorption (refractive index changes) coefficients of a donor impurity in multilayer cylindrical
quantum dots (MCQDs), under the effect of temperature T and hydrostatic pressure P.
Moreover, in this study, we also examined the effect of structure parameters on the optical absorption
coefficients of the system. The Schr€odinger equation describing the system is solved
numerically by the finite element method (FEM) within the effective mass approximation. In our
calculations, the confinement potential is modeled by a parabolic form in the radial direction and a
square one in the z-direction. The optical absorption coefficients and refractive index changes have
been investigated versus the quantum dot radius, indium composition and intensity of the incident
electromagnetic for three allowed transitions: 1s - 1p, 2s - 1p and 1p - 1d. Our essential outcomes
exhibit that the optical absorption coefficients and refractive index changes are strongly sensitive
to the variation of quantum dot sizes, which enhance and blueshift as the quantum confinement is
strong. On the contrary, the optical absorption coefficients and refractive index changes diminish
and redshift as the quantum confinement reduces.