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arXiv · 2006.14686

Quantum motion of a squeezed mechanical oscillator attained via a optomechanical experiment

P. Vezio·A. Chowdhury·M. Bonaldi·A. Borrielli·F. Marino·B. Morana·G. A. Prodi·P. M. Sarro·E. Serra·F. Marin
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Abstract

We experimentally investigate a mechanical squeezed state realized in a parametrically-modulated membrane resonator embedded in an optical cavity. We demonstrate that a quantum characteristic of the squeezed dynamics can be revealed and quantified even in a moderately warm oscillator, through the analysis of motional sidebands. We provide a theoretical framework for quantitatively interpreting the observations and present an extended comparison with the experiment. A notable result is that the spectral shape of each motional sideband provides a clear signature of a quantum mechanical squeezed state without the necessity of absolute calibrations, in particular in the regime where residual fluctuations in the squeezed quadrature are reduced below the zero-point level.

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P. Vezio, A. Chowdhury, M. Bonaldi, A. Borrielli, F. Marino, B. Morana, G. A. Prodi, P. M. Sarro, E. Serra, F. Marin. 2020-06-25. Quantum motion of a squeezed mechanical oscillator attained via a optomechanical experiment. https://doi.org/10.1103/physreva.102.053505

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