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Optical microsphere resonators: optimal coupling to high-Q whispering gallery modes

Michael L. Gorodetsky·Vladimir S. Ilchenko
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Abstract

A general model is presented for coupling of high-$Q$ whispering-gallery modes in optical microsphere resonators with coupler devices possessing discrete and continuous spectrum of propagating modes. By contrast to conventional high-Q optical cavities, in microspheres independence of high intrinsic quality-factor and controllable parameters of coupling via evanescent field offer variety of regimes earlier available in RF devices. The theory is applied to the earlier-reported data on different types of couplers to microsphere resonators and complemented by experimental demonstration of enhanced coupling efficiency (about 80%) and variable loading regimes with Q>10^8 fused silica microspheres.

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Michael L. Gorodetsky, Vladimir S. Ilchenko. 1998-05-23. Optical microsphere resonators: optimal coupling to high-Q whispering gallery modes. https://doi.org/10.1364/josab.16.000147

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