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arXiv · 1604.08367

Topological state engineering by potential impurities on chiral superconductors

Vardan Kaladzhyan·Joel Röntynen·Pascal Simon·Teemu Ojanen
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Abstract

In this work we consider the influence of potential impurities deposited on top of two-dimensional chiral superconductors. As discovered recently, magnetic impurity lattices on an $s$-wave superconductor may give rise to a rich topological phase diagram. We show that similar mechanism takes place in chiral superconductors decorated by non-magnetic impurities, thus avoiding the delicate issue of magnetic ordering of adatoms. We illustrate the method by presenting the theory of potential impurity lattices embedded on chiral $p$-wave superconductors. While a prerequisite for the topological state engineering is a chiral superconductor, the proposed procedure results in vistas of nontrivial descendant phases with different Chern numbers.

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Vardan Kaladzhyan, Joel Röntynen, Pascal Simon, Teemu Ojanen. 2016-04-28. Topological state engineering by potential impurities on chiral superconductors. https://doi.org/10.1103/physrevb.94.060505

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