Imaging the lateral shift of a quantum point contact using scanning gate microscopy

S. Schnez, C. Rössler, T. Ihn, K. Ensslin, C. Reichl, W. Wegscheider
2011 Physical Review B  
We perform scanning-gate microscopy on a quantum-point contact. It is defined in a high-mobility two-dimensional electron gas of an AlGaAs/GaAs heterostructure, giving rise to a weak disorder potential. The lever arm of the scanning tip is significantly smaller than that of the split gates defining the conducting channel of the quantum-point contact. We are able to observe that the conducting channel is shifted in real space when asymmetric gate voltages are applied. The observed shifts are
more » ... istent with transport data and numerical estimations.
doi:10.1103/physrevb.84.195322 fatcat:c53eno3y2nh27mqld53velfhzq