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Demonstration of ultra-high-Q small mode volume toroid microcavities on a chip

T. J. Kippenberg·S. M. Spillane·K. J. Vahala
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Abstract

Optical microcavities confine light spatially and temporally and find application in a wide range of fundamental and applied studies. In many areas, the microcavity figure of merit is not only determined by photon lifetime (or the equivalent quality-factor, Q), but also by simultaneous achievement of small mode volume V . Here we demonstrate ultra-high Q-factor small mode volume toroid microcavities on-a-chip, which exhibit a Q/V factor of more than $10^{6}(λ/n)^{-3}$. These values are the highest reported to date for any chip-based microcavity. A corresponding Purcell factor in excess of 200 000 and a cavity finesse of $2.8\times10^{6}$ is achieved, demonstrating that toroid microcavities are promising candidates for studies of the Purcell effect, cavity QED or biochemical sensing

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T. J. Kippenberg, S. M. Spillane, K. J. Vahala. 2004-12-07. Demonstration of ultra-high-Q small mode volume toroid microcavities on a chip. https://doi.org/10.1063/1.1833556

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