Deterministic secure quantum communication using Greenberger-Horne-Zeilinger GHZ4 state

We propose a deterministic secure quantum communication scheme by using Greenberger-Horne-Zeilinger GHZ₄ states. The scheme consists of sharing the correlation of four particle GHZ₄ states between the legitimate users. After ensuring the security of the quantum channel, they begin to exchange the secret information according to their four-particle projective measurements and classical information. The security of the present scheme against many attacks is also discussed.