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arXiv · 1511.07493

Symmetry and topology of two-dimensional noncentrosymmetric superconductors

K. V. Samokhin
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Abstract

We present a detailed study of the gap symmetry and the quasiparticle wave function topology in two-dimensional superconductors without inversion center. The strong spin-orbit coupling of electrons with the crystal lattice makes it necessary to describe superconductivity in terms of one or more nondegenerate bands characterized by helicity. We develop a topological classification of the superconducting states using the integer-valued Maurer-Cartan invariants and the Bogoliubov Wilson loops, and also calculate the spectrum of fermionic boundary modes.

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K. V. Samokhin. 2015-11-23. Symmetry and topology of two-dimensional noncentrosymmetric superconductors. https://doi.org/10.1103/physrevb.92.174517

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