Topological superconductivity and high Chern numbers in 2D ferromagnetic Shiba lattices

Joel Röntynen; Teemu Ojanen

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arXiv · 1412.5834

Topological superconductivity and high Chern numbers in 2D ferromagnetic Shiba lattices

Joel Röntynen·Teemu Ojanen

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Abstract

Inspired by the recent experimental observation of topological superconductivity in ferromagnetic chains, we consider a dilute 2D lattice of magnetic atoms deposited on top of a superconducting surface with a Rashba spin-orbit coupling. We show that the studied system supports a generalization of $p_x+ip_y$ superconductivity and that its topological phase diagram contains Chern numbers higher than $\xi/a$ $(\gg1)$, where $\xi$ is the superconducting coherence length and $a$ is the distance between the magnetic atoms. The signatures of nontrivial topology can be observed by STM spectroscopy in finite-size islands.

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Joel Röntynen, Teemu Ojanen. 2014-12-18. Topological superconductivity and high Chern numbers in 2D ferromagnetic Shiba lattices. https://arxiv.org/abs/1412.5834

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