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arXiv · 2302.03240

Transport effects in non-Hermitian nonreciprocal systems: General approach

Hamed Ghaemi-Dizicheh
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Abstract

In this paper, we present a unifying analytical framework for identifying conditions for transport effects such as reflectionless and transparent transport, lasing, and coherent perfect absorption in non-Hermitian nonreciprocal systems using a generalized transfer matrix method. This provides a universal approach to studying the transport of tight-binding platforms, including higher-dimensional models and those with an internal degree of freedom going beyond the previously studied case of one-dimensional chains with nearest-neighbor couplings. For a specific class of tight-binding models, the relevant transport conditions and their signatures of non-Hermitian, nonreciprocal, and topological behavior are analytically tractable from a general perspective. We investigate this class and illustrate our formalism in a paradigmatic ladder model where the system's parameters can be tuned to adjust the transport effect and topological phases.

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Hamed Ghaemi-Dizicheh. 2023-02-07. Transport effects in non-Hermitian nonreciprocal systems: General approach. https://doi.org/10.1103/physrevb.107.125155

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