Identity authentication by entanglement swapping in controlled quantum teleportation

Abstract

Controlled quantum teleportation (CQT) is to realise communication between a sender Alice and a receiver Bob to cooperate with a controller Charlie. It can send any quantum state α|0〉 + β|1〉 successfully by this quantum communication system. However, its drawback is that Alice can not confirm Charlie’s and Bob’s identities. In this paper, we design two identity authentication schemes IA_C and IA_B based on entanglement swapping to make identification confirmation for Charlie and Bob, and use decoy states to check outside eavesdropping. Alice confirms the identity of Charlie by using two Bell states entanglement swapping. Moreover, the identity confirmation of Bob by Alice with the help of Charlie is to use three Bell states entanglement swapping. The scheme can effectively prevent forgery identity attack to ensure the security of quantum teleportation. We also propose an improved controlled quantum teleportation (ICQT) scheme with decoy states to ensure the security of quantum channel.