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arXiv · 2005.03533

Fundamental thermal noise limits for optical microcavities

Christopher Panuski·Dirk Englund·Ryan Hamerly
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Abstract

We present a joint theoretical and experimental characterization of thermo-refractive noise in high quality factor ($Q$), small mode volume ($V$) optical microcavities. Analogous to well-studied stability limits imposed by Brownian motion in macroscopic Fabry-Perot resonators, microcavity thermo-refractive noise gives rise to a mode volume-dependent maximum effective quality factor. State-of-the-art fabricated microcavities are found to be within one order of magnitude of this bound. We confirm the assumptions of our theory by measuring the noise spectrum of high-$Q/V$ silicon photonic crystal cavities and apply our results to estimate the optimal performance of proposed room temperature, all-optical qubits using cavity-enhanced bulk material nonlinearities.

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Christopher Panuski, Dirk Englund, Ryan Hamerly. 2020-05-07. Fundamental thermal noise limits for optical microcavities. https://doi.org/10.1103/physrevx.10.041046

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