On the implementation of a deterministic secure coding protocol using polarization entangled photons

We demonstrate a prototype-implementation of deterministic information encoding for quantum key distribution (QKD) following the ping-pong coding protocol [K. Bostrom, T. Felbinger, Phys, Rev. Lett. 89 (2002) 187902-1]. Due to the deterministic nature of this protocol the need for post-processing the key is distinctly reduced compared to non-deterministic Protocols. In the course of our implementation we analyze the practicability of the protocol and discuss some security aspects of information transfer in such a deterministic scheme. (c) 2008 Elsevier B.V. All rights reserved.