We introduce a new relativistic orthogonal states quantum key distribution
protocol which leverages the properties of both quantum mechanics and special
relativity to securely encode multiple bits onto the spatio-temporal modes of a
single photon. If the protocol is implemented using a single photon source, it
can have a key generation rate faster than the repetition rate of the source,
enabling faster secure communication than is possible with existing protocols.
Further, we provide a proof that the protocol is secure and give a method of
implementing the protocol using line-of-sight and fiber optic channels.Comment: 6 pages, 2 figures. To appear in QIC Vol. 14 No. 13 & 14, pp.
1081-108
