arXiv:2311.03060 · Physical Review A

Proposal for observing nonclassicality in highly excited mechanical oscillators by single photon detection

Kai Ryen Bush, Kjetil Børkje

Published Apr 3, 2024• 4 citations

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.

DOI: 10.1103/physreva.109.043505

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