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arXiv · 2312.03997

Asymmetrical post quench transport in an embedded parity time symmetric Su-Schrieffer-Heeger system

Anirban Ghosh·Andy Martin
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Abstract

We study the effect of PT-symmetric non-hermiticity on the transport of edge state probability density arising as a result of a quench. A hybrid system involving a PT-symmetric SSH region sandwiched between two plain SSH systems is designed to study the dynamics. Geometrical arguments and numerical calculations were made to ascertain the nature of edge states. We then compute the quench dynamics numerically and demonstrate that the post-quench probability density light cones exhibit contrasting shapes as a result of asymmetrical reflections from the non-Hermitian part of the system depending on the direction of propagation of the transporting wave and, hence, on the initial localization of the edge state.

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Anirban Ghosh, Andy Martin. 2023-12-07. Asymmetrical post quench transport in an embedded parity time symmetric Su-Schrieffer-Heeger system. https://arxiv.org/abs/2312.03997

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