Atom- photon entanglement beyond the multi-photon resonance condition

摘要

The density matrix equations of motion in near-degenerate three-level V-typeclosed-loop atomic system are calculated numerically in Floquet frame. Thedynamical behavior of atom- photon entanglement between the dressed atom andits spontaneous emission is studied in semi classical approach beyond thetwo-photon resonance condition in such a system. The quantum entropy of thesetwo subsystems is investigated by using the von Neumann entropy. It is shownthat, the degree of entanglement measure (DEM) can be controlled via theintensity and the detuning of coupling optical field and quantum interferenceinduced by spontaneous emission. Moreover in the absence of quantuminterference the steady state behavior of DEM can be achieved even in beyondthe two- photon resonance condition. Furthermore in the absence of quantuminterference for special parameters of Rabi frequency and detuning of drivinglaser field disentanglement can be occurred. Also the electromagneticallyinduced transparency condition can be obtained when the system is disentangled.