title: Closing the detection loophole in Bell experiments using qudits.
abstract: 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.
authors.affiliation: Institute of Nuclear Research of the Hungarian Academy of Sciences, H-4001 Debrecen, P.O. Box 51, Hungary.
authors.forename: Tamás
authors.initials: T
authors.lastname: Vértesi
authors.forename: Stefano
authors.initials: S
authors.lastname: Pironio
authors.forename: Nicolas
authors.initials: N
authors.lastname: Brunner