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arXiv · 1808.10061

Majorana bound state localization and energy oscillations for magnetic impurity chains on conventional superconductors

Andreas Theiler·Kristofer Björnson·Annica M. Black-Schaffer
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Abstract

We study a chain of magnetic impurities on a conventional superconductor with spin-orbit coupling, treating the superconducting order fully self-consistently. We find and quantify strong hybridization between the topological edge Majorana bound states (MBSs) and in-gap Yu-Shiba-Rusinov (YSR) states, which causes increasing energy oscillations as a function of magnetic impurity strength, even when the direct MBS overlap is negligible. By treating the MBS as a topological boundary state, dependent only on the effective mass gap, we arrive at a fully parameter-free functional form of the its localization which decreases with magnetic impurity strength, opposite to the behavior of the superconducting coherence length.

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Andreas Theiler, Kristofer Björnson, Annica M. Black-Schaffer. 2019-06-25. Majorana bound state localization and energy oscillations for magnetic impurity chains on conventional superconductors. https://doi.org/10.1103/physrevb.100.214504

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