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arXiv · 2102.07483

Breaking Reciprocity in a non-Hermitian Photonic Coupler with Saturable Absorption

Dimitrios Chatzidimitriou·Alexandros Pitilakis·Traianos Yioultsis·Emmanouil E. Kriezis
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Abstract

We study the breaking of reciprocity in non-Hermitian coupled photonic waveguides by the simultaneous action of the nonlinear effect of saturable absorption, and the presence of exceptional points. The nonlinear response of such a system is studied in depth, giving physical insight into the operational principles and fundamental limitations, while producing analytical and semi-analytical results for the transmission and nonreciprocal intensity range. We numerically validate the theoretical results and assess important performance metrics for the nonreciprocal operation of such a device. This novel class of passive non-resonant devices can offer on-chip broadband nonreciprocal operation, making them potentially very important for high-speed applications.

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Dimitrios Chatzidimitriou, Alexandros Pitilakis, Traianos Yioultsis, Emmanouil E. Kriezis. 2021-02-15. Breaking Reciprocity in a non-Hermitian Photonic Coupler with Saturable Absorption. https://doi.org/10.1103/physreva.103.053503

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