Controlled Quantum Teleportation Based On Multi-Particle Entanglement State

Quantum communication is an important branch of quantum information, which includes quantum teleportation, quantum dense coding and quantum key distribution. The controlled quantum teleportation is one of the most striking direction of the quantum communication, which is the most tangible proof of the quantum non-locality. Entangled state is an important resource and an irreplaceable role in quantum communication and quantum computing. People have carried out extensive research in the general two-particle entangled states. But for multi-particle entangled states, the research are still in the exploratory stage.In order to solve the problem of communications security, coding efficiency and the practical application in quantum network, this thesis utilizes the characteristics of quantum entanglement, combines the use of the controllable quantum teleportation and hyperentanglement based on cluster states, proposes a few kinds of new schemes. As follows:Firstly, this thesis proposes a simple controlled quantum teleportation scheme based on four-particle partial entangled cluster state. Comparing with Karlsson’s scheme, the new scheme has advantages in practical quantum information processing due to make use of the cluster states. Subsequently, the above scheme will be improved in the assistance of the hyperentanglement. This thesis proposes two two-way controlled quantum teleportation schemes based on Brown cluster state. By introducing hyperentanglement, although still transmitts single-particle, but includes the freedom of the polarization degree and the spatial degrees of freedom, the carrying information is increased, improves the coding efficiency. Full duplex scheme can probabilistic achieve the intent that quantum network participants simultaneously receive and transmit quantum states. Finally, this thesis analyze the security of two-way controllable quantum teleportation schemes based on the Brown state, which turns out the proposed schemes can resist common attack strategy. In this thesis, the two-way controlled quantum teleportation schemes based on hyperentanglement Brown states can improve the quantum system channel capacity and long-distance quantum communication capabilities in a certain extent, which has practical application values for quantum communication networks.