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arXiv · 2203.01200

Observation of microcavity fine structure

C. Koks·F. B. Baalbergen·M. P. van Exter
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Abstract

We observe fine structure in the resonance spectra of optical microcavities. We identify the polarization-resolved modes in the spectrum and find that resonance frequencies split in accordance with the theoretical prediction. The observed fine structure is dominantly caused by an optical spin-orbit coupling and non-paraxial propagation and reflection. Both effects are intrinsic, i.e. present in an ideal rotation-symmetric system, and scale inversely proportional to the mirror radius of curvature. For cavities with a small radius of curvature, the influence of fine structure on the resonance spectrum is important and unavoidable and should thus be taken into account.

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C. Koks, F. B. Baalbergen, M. P. van Exter. 2022-03-02. Observation of microcavity fine structure. https://doi.org/10.1103/physreva.105.063502

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