Landau band conductivity in a two-dimensional electron system modulated by an artificial one-dimensional superlattice potential

Abstract

We investigate the magnetoresistance of a quasi-two-dimensional electron system subject to a one-dimensional superlattice potential created by field effect in gated AlGaAs/GaAs heterojunctions. At low temperatures this potential gives rise to a new type of magneto-resistance oscillations with a period governed by the ratio of the classical cyclotron diameter 2${\mathrm{R}}_{\mathrm{c}}$ to the superlattice period a. The oscillations are quantitatively explained in period, phase, and magnitude by the formation of Landau bands in the two-dimensional electron system under the influence of the periodic potential.