We present a general theoretical method to generate maximally entangled mixed states of a pair of photons initially prepared in the singlet polarization state. This method requires only local operations upon a single photon of the pair and exploits spatial degrees of freedom to induce decoherence. We report also experimental confirmation of these theoretical results.
@article{arxiv.0705.4152,
title = {Maximally Entangled Mixed-State Generation via Local Operations},
author = {A. Aiello and G. Puentes and D. Voigt and J. P. Woerdman},
journal= {arXiv preprint arXiv:0705.4152},
year = {2009}
}