Excitonic effects on the third-harmonic generation in parabolic quantum dots

Abstract
Excitonic effects on the third-harmonic-generation coefficient for disclike parabolic quantum dots are studied, and an analytic formula for the third-harmonic-generation coefficient is obtained by using the compact-density-matrix approach and an iterative method. Numerical results are presented for typical GaAs/AlGaAs parabolic quantum dots. The results show that the third-harmonic-generation coefficient is greatly enhanced because the excitons are localized in the quantum dots - it is over three times that obtained by just considering electron states - and that it is very sensitively dependent on the exciton confinement. In addition, the third-harmonic-generation coefficient is related to the relaxation constant.