Fermiology of Two-Dimensional Lateral Superlattices

Abstract

We present magnetotransport experiments on high mobility two-dimensional electron systems subjected to a weak, short period superlattice potential. The imposed periodic potential modifies the contours of constant energy of the free electrons such that new closed $k$-space trajectories, involving magnetic breakdown, become possible. Their existence is heralded by a novel type of low-field quantum oscillations.