Anomalous Proximity Effect and Theoretical Design for its Realization

Satoshi Ikegaya; Yasuhiro Asano; Yukio Tanaka

doi:10.1103/physrevb.91.174511

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arXiv · 1411.3438

Anomalous Proximity Effect and Theoretical Design for its Realization

Satoshi Ikegaya·Yasuhiro Asano·Yukio Tanaka

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Abstract

We discuss the stability of zero-energy states appearing in a dirty normal metal attached to a superconducting thin film with Dresselhaus [110] spin-orbit coupling under the in-plane Zeeman field. The Dresselhaus superconductor preserves an additional chiral symmetry and traps more than one zero-energy state at its edges. All the zero-energy states at an edge belong to the same chirality in large Zeeman field due to the effective $p$-wave pairing symmetry. The pure chiral nature in the wave function enables the penetration of the zero-energy states into the dirty normal metal with keeping their high degree of degeneracy. By applying a theorem, we prove the the perfect Andreev reflection into the dirty normal metal at the zero-energy. This paper gives a microscopic understanding of the anomalous proximity effect.

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Satoshi Ikegaya, Yasuhiro Asano, Yukio Tanaka. 2015-05-01. Anomalous Proximity Effect and Theoretical Design for its Realization. https://doi.org/10.1103/physrevb.91.174511

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