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arXiv · 2404.06143

Highly reflective and high-$Q$ thin resonant subwavelength gratings

Gurpreet Singh·Trishala Mitra·Søren P. Madsen·Aurélien Dantan
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Abstract

We theoretically investigate the design of thin subwavelength gratings possessing high-reflectivity and high-$Q$ resonances when illuminated at normal incidence by a Gaussian beam. We compare the performances of single-period and dual-period rectangular gratings using Finite Element Method-based optimization and predict one to two orders of magnitude improvement in their transmission loss-linewidth product, which is the relevant figure of merit for e.g. resonant mirror-based microcavity applications.

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Gurpreet Singh, Trishala Mitra, Søren P. Madsen, Aurélien Dantan. 2024-04-09. Highly reflective and high-$Q$ thin resonant subwavelength gratings. https://doi.org/10.1088/2515-7647%2Fad70e7

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