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arXiv · 2408.01289

Non-hermitian topology in multiterminal superconducting junctions

David Christian Ohnmacht·Valentin Wilhelm·Hannes Weisbrich·Wolfgang Belzig
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Abstract

Recent experimental advancements in dissipation control have yielded significant insights into non-hermitian Hamiltonians for open quantum systems. Of particular interest are the topological characteristics exhibited by these non-hermitian systems, that arise from exceptional points - distinct degeneracies unique to such systems. In this study, we focus on Andreev bound states in multiterminal Josephson junctions with non-hermiticity induced by normal metal or ferromagnetic leads. By investigating several systems of different synthetic dimensions and symmetries, we predict fragile and stable non-hermitian topological phases in these engineered superconducting systems.

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David Christian Ohnmacht, Valentin Wilhelm, Hannes Weisbrich, Wolfgang Belzig. 2024-08-02. Non-hermitian topology in multiterminal superconducting junctions. https://doi.org/10.1103/physrevlett.134.156601

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