Imaging the lateral shift of a quantum point contact using scanning gate microscopy
نویسندگان
چکیده
We perform scanning-gate microscopy on a quantum-point contact. It is defined in a high-mobility twodimensional 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 consistent with transport data and numerical estimations.
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