Dressed-band approach and Coulomb corrections to the light-induced exciton Stark shift

Abstract

In the present work, we perform a comparison of theoretical approaches involving Coulomb-interaction corrections within the Hartree-Fock approximation and the renormalized dressed-band scheme in the large detuning limit. We focus on the well-studied optical Stark shift of the exciton peak in bulk and GaAs-(Ga,Al)As semiconductor quantum wells. It is argued that the Hartree-Fock scheme has severe limitations concerning its application to real experimental situations, even in the simplest laser field-perturbative regime. It is also shown, through a comparison between experiments and a three-band Kane-dressed GaAs-(Ga,Al)As quantum well calculation, that a proper treatment of band structure and confinement effects due to the quantum well is of fundamental importance in a theoretical understanding of Stark shift experimental measurements, and that the renormalized dressed-band approach is a very convenient tool to treat, in the large detuning limit, processes involving the laser-semiconductor interaction in low-dimensional heterostructures. (C) 2003 American Institute of Physics.