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arXiv · 1511.08085

Andreev reflection at the edge of a two-dimentional semimetal

A. Kononov·S. V. Egorov·Z. D. Kvon·N. N. Mikhailov·S. A. Dvoretsky·E. V. Deviatov
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Abstract

We investigate electron transport through the interface between a niobium superconductor and the edge of a two-dimensional semimetal, realized in a 20~nm wide HgTe quantum well. Experimentally, we observe that typical behavior of a single Andreev contact is complicated by both a pronounced zero-bias resistance anomaly and shallow subgap resistance oscillations with $1/n$ periodicity. These results are demonstrated to be independent of the superconducting material and should be regarded as specific to a 2D semimetal in a proximity with a superconductor. We interpret these effects to originate from the Andreev-like correlated process at the edge of a two-dimensional semimetal.

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A. Kononov, S. V. Egorov, Z. D. Kvon, N. N. Mikhailov, S. A. Dvoretsky, E. V. Deviatov. 2015-11-25. Andreev reflection at the edge of a two-dimentional semimetal. https://doi.org/10.1103/physrevb.93.041303

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