| Quantum entanglement(QE) is one of the most profound features of quantum mechanics. Quantum entangled states, as a fundamental physical resource of quantum information processing, are extensively used in quantum computation and quantum communication, quantum teleportation, and quantum dense coding, etc. One of the key problems in QE study field is the generation and manipulation of quantum entangled states. It is a important and simple way to generate and manipulate entangled states in cavity QED. In this thesis, the realizations of the preparation and concentration of quantum entangled states using cavity QED system arc studied, that's to prepare maximally entangled states and to concentrate non-maximally entangled states through the interaction of the atoms and the cavity field;The entanglement dynamical properties of two entangled atoms interacting with a dissipative cavity field are studied . Some useful results are obtained:In chapter 1, some basic theories of quantum entanglement are introduced, including the presentation and definition of entangled states, serval mainly measurements of entanglement degree, manipulation of entanglement and serval kinds of entangled states.In chapter 2, the methods of preparation of atom-photon entangled states in cavity QED are expatiated and the scheme of multi-atom entangled state preparation is proposed by using cavity QED technique.In chapter 3, the method of concentrating non-maximally entangled states is proposed using cavity QED system. The concentration of remote entangled atoms is realized by using the interaction of atoms and cavity field in the large deturn condition, and the correspond scheme is also presented for the case of near entangled atoms.In chapter 4, the entanglement dynamical properties of two entangled two-level atoms interacting with a single mode field are investigated using the methods of solving master equation. We have find the scheme to remain or amplify the entanglement of entangled states which free of the cavity decay.
|
PDF Full Text Request