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Optomechanical Raman-Ratio Thermometry



Katarina Cicak, Thomas P. Purdy, Pen Li Yu, Nir Kampel, Bob Peterson, Raymond Simmonds, Cindy Regal


The temperature dependence of the asymmetry between Stokes and anti-Stokes Raman scattering can be exploited for self-calibrating, optically-based thermometry. In the context of cavity optomechanics, we observe the cavity-enhanced scattering of light interacting with the standingwave drumhead modes of a Si3N4 membrane mechanical resonator. The ratio of the amplitude of Stokes to anti-Stokes scattered light is used to measure temperatures of optically cooled mechanical modes down the level of a few vibrational quanta. We demonstrate that the Raman-ratio technique is able to measure the physical temperature of our device over a range extending from cryogenic temperatures to within an order of magnitude of room temperature.
Physical Review Letters


photon, optomechanics, raman


Cicak, K. , Purdy, T. , Yu, P. , Kampel, N. , Peterson, B. , Simmonds, R. and Regal, C. (2015), Optomechanical Raman-Ratio Thermometry, Physical Review Letters, [online], (Accessed May 24, 2024)


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Created September 8, 2015, Updated October 12, 2021