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arXiv · 1705.01718

Nematic Skyrmions in Odd-Parity Superconductors

A. A. Zyuzin·Julien Garaud·Egor Babaev
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Abstract

We study topological excitations in two-component nematic superconductors, with a particular focus on Cu$_x$Bi$_2$Se$_3$ as a candidate material. We find that the lowest-energy topological excitations are coreless vortices: a bound state of two spatially separated half-quantum vortices. These objects are nematic Skyrmions, since they are characterized by an additional topological charge. The inter-Skyrmion forces are dipolar in this model, i.e. attractive for certain relative orientations of the Skyrmions, hence forming multi-Skyrmion bound states.

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A. A. Zyuzin, Julien Garaud, Egor Babaev. 2017-10-23. Nematic Skyrmions in Odd-Parity Superconductors. https://doi.org/10.1103/physrevlett.119.167001

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