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arXiv · 2312.03825

Competing Higher Order Topological Superconducting Phases in Triangular Lattice Magnet-Superconductor Hybrid Systems

Ka Ho Wong·Jacopo Gliozzi·Mark R. Hirsbrunner·Arbaz Malik·Barry Bradlyn·Taylor L. Hughes·Dirk K. Morr
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Abstract

We demonstrate that a plethora of higher order topological phases emerge in magnet-superconductor hybrid (MSH) systems through the interplay of a stacked magnetic structure and an underlying triangular surface lattice; the latter being of great current experimental interest. Such lattices offer the ability to create three main types of edge terminations -- called x-, y- and y'-edges -- of MSH islands that, in turn, give rise to a complex phase diagrams exhibiting various regions of HOTSC phases. We identify the single adatom chain, as well as a pair of adjacent adatom chains (called a double-chain), as the basic building blocks for the emergence of HOTSC phases. Of particular interest are those HOTSC phase which arise from a competition between the topology of single and double-chain blocks, which are absent for square latices.

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Ka Ho Wong, Jacopo Gliozzi, Mark R. Hirsbrunner, Arbaz Malik, Barry Bradlyn, Taylor L. Hughes, Dirk K. Morr. 2023-12-08. Competing Higher Order Topological Superconducting Phases in Triangular Lattice Magnet-Superconductor Hybrid Systems. https://arxiv.org/abs/2312.03825

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