Optical quantum-confined Stark effect in GaAs quantum wells

Abstract

The dynamical coupling of the first two conduction-band sublevels in an 84.5-A\r{} GaAs multiple-quantum-well structure by an intense ${\mathrm{CO}}_{2}$ laser pulse leads to drastic changes in the absorption spectrum of the lowest excitons. In order to observe this new effect, the polarization of the pump laser has to be perpendicular to the plane of the layers. From the analysis of the experimental results in terms of a three-level nonlinear susceptibility the energy difference of the first two conduction-band sublevels and their transition dipole moment are determined to be 110.3 meV and 14 e\ensuremath{\cdot}A\r{}, respectively.