Journal of Atomic and Molecular Physics
Entanglement of two-mode squeezing vacuum state field interacting with atom via intensity-dependent coupling
Gao Yun-feng, Feng Jian
Abstract
Under the condition of two-mode squeezed vacuum state field interacting with an atom via the intensity-dependent coupling,the degree of entanglement between the two mode fields is investigated by using quantum relative entropy.It is found that the evolution of degree of two-mode fields entanglement is periodic.When the initial field is strong,the degree of entanglement reach maximum at scaled time gt=kπ(k=0,1,2,…),and the different between the maximum and minimum of the entanglement measures is about 1.3 generally.When the initial field is very weak,the influence of atom initial state on the entanglement evolution is sensitive.And the maximum entanglement appears under the situation of atom in a superposition state of upper level and lower level with equal probability.The entanglement of the two mode fields can be adjusted by controlling the time of the atom passing the cavity and the initial state of the atom.