The Shannon dimensionality of orbital angular momentum (OAM) entanglement produced in spontaneous parametric down-conversion can be probed by using multi-sector phase analysers. We demonstrate a spatial light modulator-based implementation of these analysers, and use it to measure a Schmidt number of about 50.
@article{arxiv.1205.4403,
title = {Determining the dimensionality of bipartite orbital-angular-momentum entanglement using multi-sector phase masks},
author = {D. Giovannini and F. M. Miatto and J. Romero and S. M. Barnett and J. P. Woerdman and M. J. Padgett},
journal= {arXiv preprint arXiv:1205.4403},
year = {2012}
}