Einstein-Podolsky-Rosen-Bohm experiment using pairs of light quanta produced by type-II parametric down-conversion

Abstract

We report a new two-photon polarization correlation experiment for realizing the Einstein-Podolsky-Rosen-Bohm (EPRB) state and for testing Bell-type inequalities. We use the pair of orthogonally polarized light quanta generated in type-II parametric down-conversion. In a 1 nm bandwidth, we observe from the output of a 0.5 mm \ensuremath{\beta}-${\mathrm{BaB}}_{2}$${\mathrm{O}}_{4}$ crystal the EPRB correlations in coincidence counts, and measure an associated Bell inequality violation of 22 standard deviations.