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Conductance anomalies in quantum wires

T. Rejec·A. Ramsak·J. H. Jefferson
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Abstract

We study the conductance threshold of clean nearly straight quantum wires in the magnetic field. As a quantitative example we solve exactly the scattering problem for two-electrons in a wire with planar geometry and a weak bulge. From the scattering matrix we determine conductance via the Landauer-Buettiker formalism. The conductance anomalies found near 0.25(2e^2/h) and 0.75(2e^2/h) are related to a singlet resonance and a triplet resonance, respectively, and survive to temperatures of a few degrees. With increasing in-plane magnetic field the conductance exhibits a plateau at e^2/h, consistent with recent experiments.

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T. Rejec, A. Ramsak, J. H. Jefferson. 2000-08-18. Conductance anomalies in quantum wires. https://doi.org/10.1088/0953-8984%2F12%2F13%2F101

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