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arXiv · 2509.23754

Nonreciprocal Coupling Induced by Nonlocal Loss Engineering

Yekai Shen·Shuhang Chen
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Abstract

Nonreciprocal coupling between photonic modes enables a range of advanced functionalities, though the available approaches for its practical implementation remain limited. Here, we introduce a novel strategy for achieving nonreciprocal coupling via nonlocal, nonlinear loss. We prove that robust, broadband, and continuously tunable nonreciprocal coupling can be realized by engineering the loss rate as a function of the state of a nonlocal mode, as validated through effective Hamiltonian modeling and numerical simulations. Our results suggest a promising route toward scalable, power-independent, and potentially integrable nonreciprocal photonic systems, with promising applications in non-Hermitian devices and topological photonics.

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Yekai Shen, Shuhang Chen. 2025-09-28. Nonreciprocal Coupling Induced by Nonlocal Loss Engineering. https://arxiv.org/abs/2509.23754

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