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arXiv · 2402.05597

Narrow-linewidth Fano microcavities with resonant subwavelength grating mirror

Trishala Mitra·Gurpreet Singh·Ali Akbar Darki·Søren Peder Madsen·Aurélien Dantan
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Abstract

We report on the theoretical and experimental investigations of optical microcavities consisting in the plane-plane arrangement of a broadband high-reflectivity mirror and a suspended one-dimensional grating mirror possessing a high-quality factor Fano resonance. By varying the length of these cavities from the millimeter to the few-micron range, we observe at short lengths the reduction of the spectral linewidth predicted to occur for such a Fano cavity as compared to a conventional broadband mirror cavity with the same length and internal losses. Such narrow linewidth and small modevolume microcavities with high-mechanical quality ultrathin mirrors will be attractive for a wide range of applications within optomechanics and sensing.

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Trishala Mitra, Gurpreet Singh, Ali Akbar Darki, Søren Peder Madsen, Aurélien Dantan. 2024-02-08. Narrow-linewidth Fano microcavities with resonant subwavelength grating mirror. https://doi.org/10.1364/oe.521329

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