Imaging signatures of the local density of states in an electronic cavity

Carolin Gold, Beat A. Bräm, Michael S. Ferguson, Tobias Krähenmann, Andrea Hofmann, Keith Fratus, Christian Reichl, Werner Wegscheider, Dietmar Weinmann, Klaus Ensslin, Thomas Ihn

Published 2020-11-27Version 1

We use Scanning Gate Microscopy to study electron transport through an open, gate-defined resonator in a Ga(Al)As heterostructure. Raster-scanning the voltage-biased metallic tip above the resonator, we observe distinct conductance modulations as a function of the tip-position and voltage. Quantum mechanical simulations reproduce these conductance modulations and reveal their relation to the partial local density of states in the resonator. Our measurements illustrate the current frontier between possibilities and limitations in imaging the local density of states in buried electron systems using scanning gate microscopy.