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arXiv · 1506.06116

Optomechanical Bell test

V. Caprara Vivoli·T. Barnea·C. Galland·N. Sangouard
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Abstract

Photons of a laser beam driving the upper motional sideband of an optomechanical cavity can decay into photon-phonon pairs by means of an optomechanical parametric process. The phononic state can subsequently be mapped to a photonic state by exciting the lower sideband, hence creating photon-photon pairs out of an optomechanical system. We here demonstrate that these pairs can violate a Bell inequality when they are measured with photon counting techniques preceded by small displacement operations in the phase space. Our results show how to detect non-local light-mechanical correlations and open the way for device-independent quantum optomechanics where non-classical light-mechanical correlations can be certified without assumptions on the state structure or on the measurement devices.

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V. Caprara Vivoli, T. Barnea, C. Galland, N. Sangouard. 2015-06-26. Optomechanical Bell test. https://doi.org/10.1103/physrevlett.116.070405

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