We show that the detection efficiencies required for closing the detection loophole in Bell tests can be significantly lowered using quantum systems of dimension larger than two. We introduce a series of asymmetric Bell tests for which an efficiency arbitrarily close to 1/N can be tolerated using N-dimensional systems, and a symmetric Bell test for which the efficiency can be lowered down to 61.8% using four-dimensional systems. Experimental perspectives for our schemes look promising considering recent progress in atom-photon entanglement and in photon hyperentanglement.
@article{arxiv.0909.3171,
title = {Closing the detection loophole in Bell experiments using qudits},
author = {Tamas Vertesi and Stefano Pironio and Nicolas Brunner},
journal= {arXiv preprint arXiv:0909.3171},
year = {2010}
}