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arXiv · 2302.13561

Topological phase diagrams of exactly solvable non-Hermitian interacting Kitaev chains

Sharareh Sayyad·Jose L. Lado
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Abstract

Many-body interactions give rise to the appearance of exotic phases in Hermitian physics. Despite their importance, many-body effects remain an open problem in non-Hermitian physics due to the complexity of treating many-body interactions. Here, we present a family of exact and numerical phase diagrams for non-Hermitian interacting Kitaev chains. In particular, we establish the exact phase boundaries for the dimerized Kitaev-Hubbard chain with complex-valued Hubbard interactions. Our results reveal that some of the Hermitian phases disappear as non-Hermiticty is enhanced. Based on our analytical findings, we explore the regime of the model that goes beyond the solvable regime, revealing regimes where non-Hermitian topological degeneracy remains. The combination of our exact and numerical phase diagrams provides an extensive description of a family of non-Hermitian interacting models. Our results provide a stepping stone toward characterizing non-Hermitian topology in realistic interacting quantum many-body systems.

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Sharareh Sayyad, Jose L. Lado. 2023-02-27. Topological phase diagrams of exactly solvable non-Hermitian interacting Kitaev chains. https://doi.org/10.1103/physrevresearch.5.l022046

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