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arXiv · 2011.11032

Boundary effects in two-band superconductors

Andrea Benfenati·Albert Samoilenka·Egor Babaev
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Abstract

We present a microscopic study of the behavior of the order parameters near boundaries of a two-band superconducting material, described by the standard tight-binding Bardeen-Cooper-Schrieffer model. We find superconducting surface states. The relative difference between bulk and surface critical temperatures is a nontrivial function of the interband coupling strength. For superconductors with weak interband coupling, boundaries induce variations of the gaps with the presence of multiple length scales, despite non-zero interband Josephson coupling.

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Andrea Benfenati, Albert Samoilenka, Egor Babaev. 2020-11-22. Boundary effects in two-band superconductors. https://doi.org/10.1103/physrevb.103.144512

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