Loophole-Free Test of Quantum Nonlocality with Continuous Variables of Light

Abstract

It is shown that a loophole-free Bell test can be achieved using continuous variables of light. A feasible optical setup is proposed for this purpose, based on a non-Gaussian state of light and high-eciency homodyne 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 singlephoton 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 electronic 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.