Quantum signature scheme with single photons

Abstract

Quantum digital signature is the quantum scenario of classical digital signature. It makes use of quantum effects to provide unconditionally secure signature. We first present a prototype of quantum signature scheme using single photons and then discuss its extensions. The most important property of the proposed scheme is that it is not necessary for the scheme to use entangled states. The security of the scheme is based on quantum key distribution and quantum one-time pad proved as unconditionally secure. The present scheme is efficient in that it needs only single photons and von Neumann measurement. We also show a quantum circuit for the scheme.