title: Experimental two-photon, three-dimensional entanglement for quantum communication.
abstract: Orbital angular momentum entangled photons emitted by a down-conversion source are in higher dimensional entangled states. Here we report the experimental confirmation by demonstrating a violation of a generalized Clauser-Horne-Shimony-Holt-type Bell inequality in three dimensions by more than 18 standard deviations. Higher dimensional entangled states allow the realization of new types of quantum communication protocols. They also provide a more secure quantum cryptography scheme. Therefore our experimental results are likely to have applications in future quantum communication technology.
authors.affiliation: Institut für Experimentalphysik, Universität Wien, Boltzmanngasse 5, Austria.
authors.forename: Alipasha
authors.initials: A
authors.lastname: Vaziri
authors.forename: Gregor
authors.initials: G
authors.lastname: Weihs
authors.forename: Anton
authors.initials: A
authors.lastname: Zeilinger