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Microtorus: a High Finesse Microcavity with Whispering-Gallery Modes

Vladimir S. Ilchenko·Michael L. Gorodetsky·X. Steve Yao·Lute Maleki
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Abstract

We have demonstrated a 165 micron oblate spheroidal microcavity with free spectral range 383.7 GHz (3.06nm), resonance bandwidth 25 MHz (Q ~ 10^7) at 1550nm, and finesse F > 10^4. The highly oblate spheroidal dielectric microcavity combines very high Q-factor, typical of microspheres, with vastly reduced number of excited whispering-gallery (WG) modes (by two orders of magnitude). The very large free spectral range in the novel microcavity - few hundred instead of few GigaHertz in typical microspheres - is desirable for applications in spectral analysis, narrow-linewidth optical and RF oscillators, and cavity QED.

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Vladimir S. Ilchenko, Michael L. Gorodetsky, X. Steve Yao, Lute Maleki. 2000-09-28. Microtorus: a High Finesse Microcavity with Whispering-Gallery Modes. https://doi.org/10.1364/ol.26.000256

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