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arXiv · 1511.07232

Chern mosaic - topology of chiral superconductivity on ferromagnetic adatom lattices

Joel Röntynen·Teemu Ojanen
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Abstract

In this work we will explore the properties of superconducting surfaces decorated by two-dimensional ferromagnetic adatom lattices. As discovered recently [R\"ontynen and Ojanen, Phys. Rev. Lett. \textbf{114}, 236803 (2015)], in the presence of a Rashba spin-orbit coupling these systems may support topological superconductivity with complex phase diagrams and high Chern numbers. We show how the long-range hopping nature of the effective low-energy theory generically gives rise to a phase diagram covered by a \emph{Chern mosaic} -- a rich pattern of topological phases with large Chern numbers. We study different lattice geometries and the dependence of energy gaps and abundance of different phases as a function of system parameters. Our findings establish the studied system as one of the richest platforms for topological matter known to date.

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Joel Röntynen, Teemu Ojanen. 2015-11-23. Chern mosaic - topology of chiral superconductivity on ferromagnetic adatom lattices. https://doi.org/10.1103/physrevb.93.094521

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