LOOPHOLE-FREE TEST OF QUANTUM NONLOCALITY WITH CONTINUOUS VARIABLES OF LIGHT

It is shown that a loophole-free Bell test can be achieved using con-tinuous variables of light. A feasible optical setup is proposed for this purpose, based on a non-Gaussian state of light and high-eciency ho-modyne detectors. The non-Gaussian entangled state can be generated from a two-mode squeezed vacuum state by subtracting a single photon from each mode using beam splitters and standard low-eciency single-photon detectors. A Bell violation exceeding 1 % can be attained with 6 dB squeezed light and an homodyne eciency around 95%. A detailed feasibility analysis, including the eect of the detector eciency, the elec-tronic noise, the impurity of the non-Gaussian state, and the probability of false triggers, suggests that this method opens a promising avenue towards a complete experimental Bell test. 1