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Proposal for a loophole-free Bell test using homodyne detection

R. Garcia-Patron Sanchez·J. Fiurasek·N. J. Cerf·J. Wenger·R. Tualle-Brouri·Ph. Grangier
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Abstract

We propose a feasible optical setup allowing for a loophole-free Bell test with efficient homodyne detection. A non-gaussian entangled state is generated from a two-mode squeezed vacuum by subtracting a single photon from each mode, using beamsplitters and standard low-efficiency single-photon detectors. A Bell violation exceeding 1% is achievable with 6-dB squeezed light and an homodyne efficiency around 95%. A detailed feasibility analysis, based upon the recent generation of single-mode non-gaussian states, confirms that this method opens a promising avenue towards a complete experimental Bell test.

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R. Garcia-Patron Sanchez, J. Fiurasek, N. J. Cerf, J. Wenger, R. Tualle-Brouri, Ph. Grangier. 2004-03-26. Proposal for a loophole-free Bell test using homodyne detection. https://doi.org/10.1103/physrevlett.93.130409

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