MAGNETIC-FIELD-INDUCED CHARGE LOCALIZATION IN A HIGH-MOBILITY SEMICONDUCTOR SUPERLATTICE

The charge distribution of mobile carriers in a high-mobility superlat tice is investigated in magnetic fields parallel to the layers. Using a capacitance-voltage profiling technique we are able to directly prob e the charge-density distribution as a function of spatial coordinate. With increasing in-plane magnetic field, we observe an increased loca lization in the potential wells of the superlattice. Using a simple mo del for the carrier distribution in the superlattice, we are able to c alculate the magnetic-field dependence of the miniband structure in th e sample. A tight-binding approach results in a quantitative descripti on of the energy level separation as a function of the in-plane magnet ic field.