We produce polarization entangled states with variable degree of entanglement for twin photons. Entanglement in polarization is coupled to entanglement in position that produces transverse coincidence interference fringes. We show both theoretically and experimentally that, due to this coupling, we can use the interference pattern to measure the polarization degree of entanglement.
@article{arxiv.quant-ph/0102023,
title = {Measurement of the degree of Polarization Entanglement Through Position Interference},
author = {M. Franca Santos and P. Milman and A. Z. Khoury and P. H. Souto Ribeiro},
journal= {arXiv preprint arXiv:quant-ph/0102023},
year = {2009}
}