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arXiv · 2001.08123

Majorana modes in multiband superconducting quantum wires

K. V. Samokhin
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Abstract

We calculate analytically the spectrum of the Andreev bound states in a half-infinite superconducting wire with an arbitrary number of bands crossing the chemical potential. The normal state of the wire is assumed to have an antiunitary symmetry A (time reversal or its combination with a crystallographic point group operation), with A^2=-1 or +1. This symmetry may be broken by the superconducting order parameter and/or the boundary scattering. We present a model-independent proof of the existence of one Majorana mode near the end of the wire with an odd number of bands.

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K. V. Samokhin. 2020-01-22. Majorana modes in multiband superconducting quantum wires. https://doi.org/10.1103/physrevb.101.094502

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