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arXiv · 1605.06541

Multimode optomechanical system in the quantum regime

William H. P. Nielsen·Yeghishe Tsaturyan·Christoffer B. Møller·Eugene S. Polzik·Albert Schliesser
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Abstract

We realise a simple and robust optomechanical system with a multitude of long-lived ($Q>10^7$) mechanical modes in a phononic-bandgap shielded membrane resonator. An optical mode of a compact Fabry-Perot resonator detects these modes' motion with a measurement rate ($96~\mathrm{kHz}$) that exceeds the mechanical decoherence rates already at moderate cryogenic temperatures ($10\,\mathrm{K}$). Reaching this quantum regime entails, i.~a., quantum measurement backaction exceeding thermal forces, and thus detectable optomechanical quantum correlations. In particular, we observe ponderomotive squeezing of the output light mediated by a multitude of mechanical resonator modes, with quantum noise suppression up to -2.4 dB (-3.6 dB if corrected for detection losses) and bandwidths $\lesssim 90\,\mathrm{ kHz}$. The multi-mode nature of the employed membrane and Fabry-Perot resonators lends itself to hybrid entanglement schemes involving multiple electromagnetic, mechanical, and spin degrees of freedom.

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William H. P. Nielsen, Yeghishe Tsaturyan, Christoffer B. Møller, Eugene S. Polzik, Albert Schliesser. 2016-05-20. Multimode optomechanical system in the quantum regime. https://doi.org/10.1073/pnas.1608412114

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