| Entanglement is one of the most striking features of quantum mechanics, and plays key pole in quantum information science. Quantum entanglement, as a physical resource, lies at the heart of quantum computation, quantum communication, quantum teleportation, and quantum superdense-coding. However, a maximally entangled state prepared for quantum information processing which is inevitablly interact with the environment, will easily become into a non-maximally entangled state. With this non-maximally entangled state in quantum communication and computation, the informat--ion is distorted. To overcome the above obstacle, entanglement purification become critical in quantum teleportation. In this paper, with the feature of intrinsic decoherence , the system of atom inter--acting with two distinct optical cavities is discussed. It is also studied the differences on the effect of the phase decoherence rate on the fidelity between before and after the system purificiation.Then, the maximal fidelity of quantum teleportation can be achieved.In this paper, quantum teleportation and entanglement purification will be discussed in detail. Firstly, some basic theories of quantum teleporation are introduced in chapter 2, including the presentation and definition of entangled states, the definition of fidelity, the physical source and matter of decoherence. In chapter 3, the methods of entanglement purification are introduced, including local Controlled-Not (CNOT) operation and local Positive Operator-Valued Measuer (POVM). In chapter 4, the entanglement purification protocol for the system of atom interacting with two distinct optical cavities is discussed. The fidelities before and after the system purification are studied. The results indicate that the effect of the phase decoherence rate and detuning parameter on the fidelity can be reduced by modifying two quantum logical gates.Then, maximal fidelity of quantum teleportation can be achieved...
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