Interplay between the periodic potential modulation and random background scatterers in an antidot lattice

Antidot lattices with top and back gate tunability allow the electronic transport properties of a sample to be studied at a constant electron density while the two-dimensional electron system is shifted in the z direction. The antidot potential is found to remain essentially unaltered in our sample during a constant density sweep, while other parameters such as the background mobility or wave function symmetry in the z direction vary. The impact of these changes on the classical commensurability peaks, the Aharonov-Bohm-type oscillations, and on a weak-localization-type feature around B=0 T are investigated. In addition, a peak splitting appears in oscillations superimposed on the main commensurability peak at high electron densities.