Kerr nonlinearity in asymmetric disc-like quantum dot and its controllability

Abstract

Nonlinear Kerr materials have the potential to be used as principal components for developing optical quantum computers. Among these materials, quantum dots have high nonlinearity and high Kerr-dispersion. This paper investigated the Kerr effect in a doped asymmetric quantum dot. The results showed that third-order nonlinear optical property such as the Kerr effect can be controlled by Rashba coupling. Experimentally, the strength of Rashba coupling can be changed and thus manipulated by applying a voltage to the electrostatic gate installed on the two-dimensional plane of quantum dots. The numerical calculations illustrated that the presence of attractive impurity and enhancement of the strength of Rashba coupling in an asymmetric quantum dot increase the Kerr nonlinearity. Furthermore, the results demonstrated that the magnitude of the Kerr effect of a symmetric doped quantum dot is larger than an asymmetric doped quantum dot.