T-C模型中有耦合的两二能级原子的纠缠度

纠缠度是对被纠缠的子系统之间的关联程度的量度.用冯?诺依曼熵来描述在相干光场中两 耦合二能级原子之间的纠缠度的演化，显示了两二能级原子之间的纠缠度与原子之间的耦合 强度，光场与原子之间的失谐量的大小以及场强有关系.对初始处于贝尔基的两个原子，原 子间耦合的增强和失谐量的增加都将使纠缠度增加，纠缠度振荡的频率增加，而光强的增强 将导致原子间纠缠度的下降.

Entanglement of Two Coupled Two-Level Atoms in Tavis-Cummings Model

Entanglement is used to measure correlation between entangled subsystems.In this paper,we use Von Neumann entropy to study evolution of the entanglement for two coupled dual-level atoms in the process of interaction between atoms and the field initially prepared in a coherent state.We show that the entanglement is related to coupled strength,detuning and intensity of the field.For two atoms initially prepared in the Bell basis,with coupled strength between two atoms and detuning between atoms and the field increased,entanglement and its oscillating frequency will increase.But increasing the intensity of the field leads to decrease of entanglement.