Controlled Quantum Teleportation of a One-Particle Unknown State via a Three-Particle Entangled State

<正> A kind of three-particle entangled state is applied as quantum channel of the controlled quantum telepor-tation of a one-particle unknown state.The one-particle unknown state is transmitted from the sender to the recipientunder the control of the supervisor.After the sender makes Bell-state measurement and the supervisor performs vonNeumann measurement,the recipient carries out unitary transformation on his own particle depending on classical in-formation from the sender and the supervisor.The teleportation cannot be completed successfully by the recipient ifthe supervisor does not agree to cooperate.The roles of the recipient and the supervisor may be exchanged in thisscheme.The scheme is flexible and feasible because the sequence of manipulation of the sender and the supervisor maybe exchanged and only simple unitary transformation is included.