Study On Quantum Teleportation And Cavity QED

Quantum information is a new interdisciplinary subject that is a com-bination of quantum mechanics and classic information science. Quantuminformation, which based on the basictheory of state superposition principle ofquantum mechanics, mainly researches information management. It includesquantum cryptography, quantum communication and quantum computer andso on.Quantum teleportation is one of the most striking fields in quantumcommunication, and also a novel and interesting application of quantum me-chanics.So study on quantum teleportation is very meaningfulnot only to thedevelopment of quantum communication, but also to apprehending the insideof mechanics more deeply, which can promote its developement.In this paper, we have proposed some schemes for implementation of tele-portation,and as follows:1. The teleportation of an arbitrary n-particle state. We proposed ascheme for teleportation of an arbitrary n-particle state by using n Einstein-Podolsky-Rosen (EPR) pairs as its quantum channel. In this scheme, we havefound out the internal relation between the Bell measurement results operatedby the sender Alice and the transformation performed by the receiver Bob,thereby, the receiver Bob can take the proper transformation on his particlesaccording to the measurement results, and finish the task of teleportationsuccessfully. For the case of n→∞, this way of teleportation is quite ofimportance. Similarily, this scheme can be easily generalized to teleport anarbitrary n-particle d-level state. Namely, we can teleport multi-paticle andmulti-level state by using n general Bell state as its quantum channel.2. The probable teleportation of a single qubit state. In this scheme, wehave investigated the maximally probable teleportation of an unkown quantumstate between the two-level atoms in cavity QED. Because the atom interactwith a great detunning vacumn cavity, this sheme is insensitive to the thermalfield and cavity decay. 3. The perfect teleportation of an arbitrary n-atom state Without Bellmeasurement within the thermal cavity. In this paper, we have presenteda feasible experimental scheme for teleportation of a arbitrary multi-particlestate. Compared with the two schemes above, this scheme dosen't need anyBell measurement and is also insensitive to the thermal field, and is slightlyaffected by the experimental error with a probability approximatting 1.0.