Magnetoresistance and temperature effects in dotlike lateral surface superlattices

Abstract

The magnetotransport in dotlike lateral surface superlattices is investigated as a function of Fermi energy and temperature. At low magnetic fields, the magnetoresistance shows a well-defined negative differential behavior, which is followed by one or two large peaks. In this regime, Hall measurements indicate that the number of electrons that contribute to the current depends strongly on the applied magnetic field. Moreover, a clear negative temperature coefficient of the magnetoresistance is observed. Both effects are explained in terms of a semiclassical picture.