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arXiv · 2201.07340

Measuring High-Order Phonon Correlations in an Optomechanical Resonator

Yogesh S. S. Patil·Jiaxin Yu·Sean Frazier·Yiqi Wang·Kale Johnson·Jared Fox·Jakob Reichel·Jack G. E. Harris
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Abstract

We use single photon detectors to probe the motional state of a superfluid $^4$He resonator of mass $\sim1$ ng. The arrival times of Stokes and anti-Stokes photons (scattered by the resonator's acoustic mode) are used to measure the resonator's phonon coherences up to the fourth order. By post-selecting on photon detection events, we also measure coherences in the resonator when $\leq3$ phonons have been added or subtracted. These measurements are found to be consistent with predictions that assume the acoustic mode to be in thermal equilibrium with a bath through a Markovian coupling.

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Yogesh S. S. Patil, Jiaxin Yu, Sean Frazier, Yiqi Wang, Kale Johnson, Jared Fox, Jakob Reichel, Jack G. E. Harris. 2022-01-18. Measuring High-Order Phonon Correlations in an Optomechanical Resonator. https://doi.org/10.1103/physrevlett.128.183601

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