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Andreev magnetotransport in low-dimensional proximity structures: Spin-dependent conductance enhancement

Grygoriy Tkachov·Klaus Richter
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Abstract

We study the excess conductance due to the superconducting proximity effect in a ballistic two-dimensional electron system subject to an in-plane magnetic field. We show that under certain conditions the interplay of the Zeeman spin splitting and the effect of a screening supercurrent gives rise to a spin-selective Andreev enhancement of the conductance and anomalies in its voltage, temperature and magnetic field characteristics. The magnetic-field influence on Andreev reflection is discussed in the context of using superconducting hybrid junctions for spin detection.

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Grygoriy Tkachov, Klaus Richter. 2004-11-16. Andreev magnetotransport in low-dimensional proximity structures: Spin-dependent conductance enhancement. https://doi.org/10.1103/physrevb.71.094517

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