AFM-defined antidot lattices with top- and back-gate tunability

Abstract

Antidot lattices with a period of 150 nm were defined by AFM lithography on a wafer with a back-gate electrode and later covered with a TiAu top-gate. This layout enabled us to study the electronic properties of the lattice at different electron densities and as a function of top- and back-gate voltage at constant Fermi energy. Commensurability peaks and Aharonov–Bohm-type oscillations were observed in the magnetoresistance and characterized under continuously varying conditions. The small lattice constant brings the classical commensurability oscillations to magnetic fields B>1.5 T , where quantum effects become important.