Electronic properties of a quasi-two-dimensional electron gas in semiconductor quantum wells under intense laser fields

Abstract

A systematic study on the influence of two intense, long-wavelength, nonresonant laser fields on the electron energy levels and density of states (DOS) in $\mathrm{GaAs}∕\mathrm{AlGaAs}$ quantum wells is performed within a Green's function approach. The carrier confinement pattern and its associated DOS are shown to be modified by the laser beams. For laser field polarizations parallel to the growth direction only the effective potential is changed whereas for in-plane polarizations only the DOS is altered in the sense that it is field-driven. The results show that for a $\mathrm{GaAs}∕\mathrm{AlGaAs}$ quantum well the effect of the laser field radiation is to induce strong blueshifts in the electronic energy levels. The DOS dependence on the laser-induced confinement characteristics changes from the usual ladder profile to a functional form that reminds us of a one-dimensional system.