Sudden Birth And Suddden Death Of The Entanglement Between Two Atoms In Double J-C Model

As it is well known that quantum entanglement is one of the most profound features of quantum mechanis.Quantum entangled states,as a fundamental physical resource of quantum information processing,are extensively used in quantum computation an quantum communication,quantum teleportation, and quantum dense coding,etc.Entanglement sudden birth and suddden death is one of the most striking field in quantum mechanics,and also a novel and interesting application of quantum computation.So study on Entanglement sudden birth and suddden death is very meaningful not only to the development of quantum mechanics,but also to apprehending the inside of quantum mechanics more deeply.In this thesis,we have studied the sudden birth and suddden death of the entanglement between two atoms in double J-C model.1,In a double J-C model,Sudden death of entanglement between two entangled atoms independently coupled to their fields is investigated in two detuning cavities.The results show that the entanglement between two atoms evolves periodically and sudden death of entanglement depends on not only the detuning but also on the two atomic initial states.And the influence of the ratio of the two atom-field coupling constants on sudden death of entanglement is discussed.2,Sudden birth of entanglement between two initially separate atoms interacting with two entangled photons in a double J-C model is investigated, and influences of different atomic initial state on entanglement,between atoms are discussed.It is found that sudden birth of entanglement can occur when the two atoms are initially in excited states.And the ratio of the two atom-field coupling constants influence on sudden death of entanglement.