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arXiv · 2407.17000

Time-Reversal Symmetry Bounds in Temporal Coupled-Mode Theory

Ken X. Wang
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Abstract

We provide a general treatment for the temporal coupled-mode theory with arbitrary numbers of modes and ports, and derive tight bounds for the coupling phases in addition to coupling strengths under time-reversal symmetry. We report trade-offs between the cardinalities of the reciprocal regions of the resonant coupling strengths versus phases. We discover that time-reversal symmetry enforces projected generalized reflections in the background to cancel out completely. In double-port systems, the reciprocal regions of the coupling phases span a quarter of the nonreciprocal regions for any non-hidden mode.

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Ken X. Wang. 2024-07-24. Time-Reversal Symmetry Bounds in Temporal Coupled-Mode Theory. https://arxiv.org/abs/2407.17000

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