Kerr效应对非线性Jaynes-Cummings模型场熵和缠结的影响

Phoenix和Knight提出的量子熵理论,用量子熵作为缠结程度的量度,研究了附加克尔介质依赖强度耦合Jaynes-Cummings模型场熵演化的动力学特性和原子-场的缠结特性,详细地讨论了克尔效应及初始相干光场的强弱对场熵演化特性和原子-场缠结特性的影响,并与原子反转特性相比较.结果表明:在初始相干光场较弱时(n=10),克尔介质的非线性相互作用破坏了场熵演化的周期性,原子-场不再周期消缠结.但在初始相干光场较强时(n=50),克尔介质非线性相互作用只是使场熵演化的周期性减弱,场熵的演化仍近似地有周期性,原子-场仍周期消缠结,克尔效应越强,周期越小.当克尔介质与光场强耦合相互作用时(χ/g=5),原子-场持续消缠结.

INFLUENCE OF KERR EFFECT ON FIELD ENTROPY AND ENTANGLEMENT IN THE INTENSITY-DEPENDENT COUPLING JAYNES-CUMMINGS MODEL

The dynamical properties of the field entropy and atom field entanglement in the intensity dependent coupling Jaynes-Cummings model with an additional Kerr medium are investigated.The influences of Kerr effect and the average photon number of initial coherent field on the field entropy and atom field entanglement are discussed in comparison with atomic inversion.The results show when the initial coherent field is not large (n=10),the periodicity of the field entropy evolution is destroied by Kerr effect,atom field is not disentangle periodicly;otherwise,when the initial coherent field is large (n=50),the field entropy evolution have periodicity approximately,the stronger Kerr effect is,the smaller the period is;when χ/g=5,atom field is disentangle all the time.