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arXiv · 2301.08446

Topological Phases in a PT-Symmetric Dissipative Kitaev Chain

Makio Kawasaki·Hideaki Obuse
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Abstract

We study a topological phase in the dissipative Kitaev chain described by the Markovian quantum master equation. Based on the correspondence between Lindbladians, which generate the dissipative time-evolution, and non-Hermitian matrices, Lindbladians are classified in terms of non-Hermitian topological phases. We find out that the Lindbladian retains PT symmetry which is the prominent symmetry of open systems and then all the bulk modes can have a common lifetime. Moreover, when open boundary conditions are imposed on the system, the edge modes which break PT symmetry emerge, and one of the edge modes has a zero eigenvalue.

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Makio Kawasaki, Hideaki Obuse. 2023-01-20. Topological Phases in a PT-Symmetric Dissipative Kitaev Chain. https://doi.org/10.7566/jpscp.38.011165

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