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Title: Transport effects in non-Hermitian nonreciprocal systems: General approach
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.  more » « less
Award ID(s):
2012172
PAR ID:
10635644
Author(s) / Creator(s):
Publisher / Repository:
APS
Date Published:
Journal Name:
Physical Review B
Volume:
107
Issue:
12
ISSN:
2469-9950
Page Range / eLocation ID:
125155
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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