Experimental demonstration of continuous variable polarization   entanglement
  We report the experimental transformation of quadrature entanglement between two optical beams into continuous variable polarization entanglement. We extend the inseparability criterion proposed by Duan, et al. [Duan00] to polarization states and use it to quantify the entanglement between the three Stokes operators of the beams. We propose an extension to this scheme utilizing two quadrature entangled pairs for which all three Stokes operators between a pair of beams are entangled. 
Warwick P. Bowen, Nicolas Treps, Roman Schnabel, Ping Koy Lam