Energy spectrum and optical properties of the quantum dot-impurity center complex

Abstract

The impurity absorption of light in the quantum dot (QD) with a spherically symmetric potential has been considered within the framework of the zero-range potential model in the effective mass approximation. The dynamics of formation of the localized D− state as a superposition of QD states with different orbital quantum number values is demonstrated. The impurity absorption coefficient is calculated taking into account the QD size dispersion, which leads to broadening of discrete impurity absorption lines. Numeric estimates of the D− state binding energy and the impurity absorption coefficient are presented for the heterophase QD system 〈CdS〉-〈transparent silicate glass matrix〉. The sensitivity of the impurity absorption edge to the impurity level depth and to the mean QD radius was studied.