%0 Journal Article %T Deterministic Secure Direct Bidirectional Communication Protocol %A Zhanjun Zhang %J Physics %D 2004 %I arXiv %X In this letter a deterministic secure direct bidirectional communication protocol is proposed by using the quantum entanglement and local unitary operations on one photon of the Einstein-Podolsky-Rosen (EPR) photon pair. %U http://arxiv.org/abs/quant-ph/0403186v1