Test of Bell-type theorems based on parity-coherent states of light fields

Abstract

We propose to test Bell-type theorems of continuous variables based on the pseudospin operator of parity-coherent states of light fields. The proposed Belltype theorem has a constant, maximal violation 2 √ 2 in the Schmidt bases for large values of the mean photon number. Continuous-variable systems usually have the advantage of high detection efficiency with the homodyne detection method. The required parity-coherent states are experimentally realizable. Using two-mode light fields entangled both in parity and polarization, we also present a proposal of all-versus-nothing test of local realism.