Effects of external fields on the far-infrared 1s→2p+ intradonor absorption spectra in quantum wells

Abstract

The effects of both electric and magnetic fields (applied perpendicular to the interfaces) on the donor transition energies on a GaAs-Ga1−xAlxAs quantum well are studied by following a variational calculation within the effective-mass approximation with two-parameter variational envelope hydrogenic wave functions for the 1s- and 2p+-like donor states. A detailed analysis of the far-infrared intradonor absorption spectra, taking into account a proper consideration of the impurity-doping profile, is performed and results are compared with recent experimental data. The agreement between the reported magnetospectroscopic data and the average photon energy at the width at half-maximum of the calculated infrared-absorption spectra is quite apparent. It is unambiguously shown that the absorption spectra must be evaluated with an adequate choice of the variational envelope wave function for a correct quantitative understanding of the experimental measurements.