Anomalous proximity effect of a spin-singlet superconductor with a spin-orbit interaction

Jaechul Lee; Satoshi Ikegaya; Yasuhiro Asano

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arXiv · 2501.17369

Anomalous proximity effect of a spin-singlet superconductor with a spin-orbit interaction

Jaechul Lee·Satoshi Ikegaya·Yasuhiro Asano

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Abstract

The anomalous proximity effect of a spin-triplet $p$-wave superconductor has been known as a part of the Majorana physics and is explained by the penetration of zero-energy states from a surface of a superconductor to a dirty normal metal. We demonstrate that a spin-singlet $d$-wave superconductor without any surface zero-energy states exhibits the anomalous proximity effect in the presence of a specific spin-orbit interaction. The results show the quantization of the zero-bias conductance in a dirty normal-metal/superconductor junction. We also discuss a relation between our findings and results in an experiment on a CoSi$_2$/TiSi$_2$ junction.

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Jaechul Lee, Satoshi Ikegaya, Yasuhiro Asano. 2025-03-21. Anomalous proximity effect of a spin-singlet superconductor with a spin-orbit interaction. https://arxiv.org/abs/2501.17369

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