title: Violations of local realism by two entangled N-dimensional systems are stronger than for two qubits
abstract: Tests of local realism versus quantum mechanics based on Bell's inequality employ two entangled qubits. We investigate the general case of two entangled quantum systems defined in N-dimensional Hilbert spaces, or " quNits." Via a numerical linear optimization method we show that violations of local realism are stronger for two maximally entangled quNits ( 3</=N</=9) than for two qubits and that they increase with N. The two quNit measurements can be experimentally realized using entangled photons and unbiased multiport beam splitters.
authors.affiliation: Instytut Fizyki Teoretycznej i Astrofizyki Uniwersytet Gdanski, PL-80-952 Gdansk, Poland.
authors.initials: D
authors.lastname: Kaszlikowski
authors.initials: P
authors.lastname: Gnacinski
authors.initials: M
authors.lastname: Zukowski
authors.initials: W
authors.lastname: Miklaszewski
authors.initials: A
authors.lastname: Zeilinger