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Shifting a Quantum Wire through a Disordered Crystal: Observation of Conductance Fluctuations in Real Space

T. Heinzel·G. Salis·R. Held·S. Luescher·K. Ensslin·W. Wegscheider·M. Bichler
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Abstract

A quantum wire is spatially displaced by suitable electric fields with respect to the scatterers inside a semiconductor crystal. As a function of the wire position, the low-temperature resistance shows reproducible fluctuations. Their characteristic temperature scale is a few hundred millikelvin, indicating a phase-coherent effect. Each fluctuation corresponds to a single scatterer entering or leaving the wire. This way, scattering centers can be counted one by one.

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T. Heinzel, G. Salis, R. Held, S. Luescher, K. Ensslin, W. Wegscheider, M. Bichler. 1999-09-23. Shifting a Quantum Wire through a Disordered Crystal: Observation of Conductance Fluctuations in Real Space. https://doi.org/10.1103/physrevb.61.r13353

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