The spectroscopic observation of D −, D 0 and cyclotron resonance lines in n-GaAs at intermediate magnetic fields

Abstract

Spectroscopic transitions originating on negatively charged donor ions ( D - states) are observed in far-infrared magneto-optic experiments with n-GaAs and compared with transitions originating from the ground state of the neutral donors, those linking excited states of the neutral donors and cyclotron resonance of the free carriers. Ten laser wavelengths between 250 and 1200 μm are employed. The magnetic field parameter γ extends up to 1.6 enabling variational calculations to be compared with experiment for the first time at intermediate fields. The intensities of the D - lines depend on experimental conditions such as temperature, electric field, optical pumping and the degree of compensation and purity of the sample. Under optimum conditions the peak heights of the D - lines are comparable with the D 0 and cyclotron resonance lines.