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arXiv · 0811.3150

Non-local Aharonov-Bohm conductance oscillations in an asymmetric quan-tum ring

S. S. Buchholz·S. F. Fischer·U. Kunze·D. Reuter·A. D. Wieck
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Abstract

We investigate ballistic transport and quantum interference in a nanoscale quantum wire loop fab-ricated as a GaAs/AlGaAs field-effect heterostructure. Four-terminal measurements of current and voltage characteristics as a function of top gate voltages show negative bend resistance as a clear signature of ballistic transport. In perpendicular magnetic fields phase-coherent transport leads to Aharonov-Bohm (AB) conductance oscillations which show equal amplitudes in the local and the non-local measurement at a temperature of 1.5 K and above. We attribute this novel observation to the symmetry of the orthogonal cross junctions connecting the four quantum wire leads with the asymmetric quantum wire ring.

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S. S. Buchholz, S. F. Fischer, U. Kunze, D. Reuter, A. D. Wieck. 2008-11-19. Non-local Aharonov-Bohm conductance oscillations in an asymmetric quan-tum ring. https://doi.org/10.1063/1.3069281

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