Effects of external perturbations on light absorption by light/heavy hole excitons in a semi-parabolic quantum well

Abstract

The effects of electric, magnetic, and intense terahertz laser fields on optoelectronic properties are inves- tigated in a GaAs/Al x Ga 1-x As semi-parabolic quantum well. The binding energy, exciton light absorption coefficients, interband transition energies, and dipole elements in the matrix are studied within the struc- ture of the parabolic band and effective-mass approximations. The transition energy difference between the ground-state electron energy level and the ground-state heavy hole (light hole) energy level and ma- trix elements are carried out as functions of external perturbations with a constant well size. The results exhibit that the exciton binding energies of heavy and light holes reduce as long as the laser dressing parameter is larger. The optical absorption of light hole exciton in the system is stronger than the heavy hole exciton. And the excitonic energies, transition energies, and absorption coefficients are much more sensitive and controlled by changing the external perturbations.