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arXiv · 2311.03060

Proposal for Observing Nonclassicality in Highly Excited Mechanical Oscillators by Single Photon Detection

Kai Ryen Bush·Kjetil Børkje
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Abstract

The preparation of pure quantum states with high degrees of macroscopicity is a central goal of ongoing experimental efforts to control quantum systems. We present a state preparation protocol which renders a mechanical oscillator with an arbitrarily large coherent amplitude in a manifestly nonclassical state. The protocol relies on coherent state preparation followed by a projective measurement of a single Raman scattered photon, making it particularly suitable for cavity optomechanics. The nonclassicality of the state is reflected by sub-Poissonian phonon statistics, which can be accessed by measuring the statistics of subsequently emitted Raman sideband photons. The proposed protocol would facilitate the observation of nonclassicality of a mechanical oscillator that moves macroscopically relative to motion at the single-phonon level.

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Kai Ryen Bush, Kjetil Børkje. 2023-11-06. Proposal for Observing Nonclassicality in Highly Excited Mechanical Oscillators by Single Photon Detection. https://doi.org/10.1103/physreva.109.043505

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