Influence of polaron effects on the ground state of weak-coupling exciton in semiconductor quantum dots

Abstract

The influence of polaron effects on the effective potential of weak-coupling exciton in semiconductor quantum dots (QDs) is studied based on the Lee-Low-Pines-Huybrechts variational method. The results show that the effective potential of the exciton consists of three parts: coulomb potential, induced potential and confining potential. Numerical calculations for the GaAs quantum dot, as an example, are performed. The result indicates that the effective potential of the exciton increases with the electron-hole distance. It is found that the polaron effects have remarkable influence on the states of the exciton: helpful to the stability of the light-hole exciton, but unfavorable to the stability of the heavy-hole exciton.

Keywords

Effective Potential / Confine Potential / Longitudinal Optical / Coupling Exciton / Polaron Effect

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This work has been supported by the Natural Science Foundation of Hebei Province (No. A2008000463).