运动强度相关耦合J-C模型中的熵交换和纠缠

考虑一个运动的二能级原子与单模热光场强度相关耦合,采用量子约化熵研究原子和场的约化熵变化规律、原子与场的熵交换,用共生纠缠度研究原子与场的纠缠。并借助于数值计算方法,详细分析了在强度相关耦合J-C模型中,原子初态、热光场的平均光子数以及场模结构参数对熵交换和纠缠的影响。结果表明原子与光场的熵交换和纠缠均周期性地演化。选择适当的原子初态,可以使得原子的约化熵和光场的约化熵完全交换,这意味着原子与光场反相关。此外,场模结构参数增加导致熵交换的幅度减小,周期缩短。原子与热光场的纠缠随平均光子数的增加而减弱。

Entropy Exchange and Entanglement in Intensity-Dependent Coupling J-C Model with Atomic Motion

Considering a moving two-level atom coupling with a single-mode thermal light field through intensity-dependence, reduced entropy change and entropy exchange between the atom and the field is studied by using quantum reduced entropy, entanglement is measured by using concurrence, the effect of initial atomic state, the mean photon number of thermal field and the field-mode structural parameter on entropy exchange and entanglement are investigated. The results show that reduced entropy change and entanglement exhibit periodic evolution. When initial parameters are suitable, the complete exchange between the atomic and field reduced entropy occurs, which means there is a form of anti-correlated behavior between field and atom. In addition, the increase of field-mode structural parameter weakens reduced entropy exchange, and shortens period of entropy exchange. Entanglement between atom and field decreases as the transition photon number increases.