title: Quantum cryptography with 3-state systems.
abstract: We consider quantum cryptographic schemes where the carriers of information are 3-state particles. One protocol uses four mutually unbiased bases and appears to provide better security than obtainable with 2-state carriers. Another possible method allows quantum states to belong to more than one basis. Security is not better, but many curious features arise.
authors.affiliation: Group of Applied Physics, University of Geneva, CH-1211, Geneva 4, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Bechmann-Pasquinucci
authors.forename: A
authors.initials: A
authors.lastname: Peres
mesh_terms: D003142:Communication; D007257:Information Theory; D011789:Quantum Theory