MAGNETOPOLARON EFFECT ON SHALLOW DONORS IN BULK GAAS AND ON D-0 AND D- IN GAAS ALGAAS SUPERLATTICES/

A theoretical study is made of the energy levels of shallow donors in bulk GaAs and in GaAs/AlGaAs superlattices in an external magnetic fie ld. The influence of magneto-polarons on these energy levels is studie d within second-order perturbation theory. Special attention is paid t o the resonant polaron interaction, and the importance of band non-par abolicity at high magnetic fields is also shown. One-electron as well as two-electron bound states of the donor are investigated. Our result s are in good agreement with available experimental far-infrared optic al data of the different transitions within the above systems.