Optical properties of a few semiconducting heterostructures in the presence of Rashba spin-orbit interactions: a two-dimensional finite-difference numerical approach

Abstract

In the present study, the effect of Rashba spin-orbit interactions on the electron energy states, spin-density distributions, and absorption coefficient of a few two-dimensional quantum dots with different confining potentials are studied. We use a finite-difference method to solve the resulting coupled Schrodinger equations. In our computations, since the concluded Hamiltonian matrix is found to be extensive; regardless of being blocked and sparse, implementing the Arnoldi factorization method for diagonalizing the Hamiltonian matrix is required. According to results, it is found that the interstate mixing that stemmed from the Rashba spin-orbit interaction can result in a new spin polarization. This occurrence explicitly justifies the observation of multiple peaks in the spin-density distributions. Furthermore, by increasing the quantum dot size, the absorption coefficient increases about 4 times. Finally, by increasing the Rashba parameter, the absorption peak decreases and a redshift takes place.