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arXiv · 2107.02321

Universal behavior of the scattering matrix near thresholds in photonics

Charles C. Wojcik·Haiwen Wang·Meir Orenstein·Shanhui Fan
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Abstract

Scattering thresholds and their associated spectral square root branch points are ubiquitous in photonics. In this Letter, we show that the scattering matrix has a simple universal behavior near scattering thresholds. We use unitarity, reciprocity, and time-reversal symmetry to construct a two-parameter model for a two-port scattering matrix near a threshold. We demonstrate this universal behavior in three different optical systems, namely a photonic crystal slab, a planar dielectric interface, and a junction between metallic waveguides of different widths.

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Charles C. Wojcik, Haiwen Wang, Meir Orenstein, Shanhui Fan. 2021-07-05. Universal behavior of the scattering matrix near thresholds in photonics. https://doi.org/10.1103/physrevlett.127.277401

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