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Generating optimal states for a homodyne Bell test

Sonja Daffer·Peter L. Knight
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Abstract

We present a protocol that produces a conditionally prepared state that can be used for a Bell test based on homodyne detection. Based on the results of Munro [PRA 1999], the state is near-optimal for Bell-inequality violations based on quadrature-phase homodyne measurements that use correlated photon-number states. The scheme utilizes the Gaussian entanglement distillation protocol of Eisert et. al. [Annals of Phys. 2004] and uses only beam splitters and photodetection to conditionally prepare a non-Gaussian state from a source of two-mode squeezed states with low squeezing parameter, permitting a loophole-free test of Bell inequalities.

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Sonja Daffer, Peter L. Knight. 2005-04-12. Generating optimal states for a homodyne Bell test. https://doi.org/10.1103/physreva.72.034101

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