Entropy Properties In The System Of Two-mode Light Field Interacting With Two Two-level Atoms

If a system contains more tan two subsystems and the function of the system can not be obtained by accumulating the functions of the subsystems, the system has been entanglement state. The quantum entanglement plays an important role in quantum communication, and it can be measured by entropy. The larger the entropy is, the larger the quantum entanglement is.The entanglement properties of the system, which is the correlated SU(1,1) coherent state light filed interacting with a pair of two-level atoms via the two-photon process, were studied by complete quantum theory in this paper. SU(1,1) coherent states has the predominant property in entanglement and compress between the two modes, so it can act as information carrier in quantum teleportation and it is meaningful to study the interaction between SU(1,1) coherent states and atoms in theory. It is found that with the increase of the parameterξrepresenting the correlation of the two modes and the representing the photon number difference in the SU(1,1) coherent states, the atom-field entanglement and the atom-atom entanglement are enhanced; On the other hand, the parameter representing the initial entanglement of the atoms coupling enhances the atom-field entanglement; The Rabi frequency and sink-reversion periods are decided by atom-filed coupling constant and atom-atom coupling constantΩ.