Kerr介质中双模纠缠相干光场与Bell态原子相互作用系统的原子布居数演化

运用全量子理论和数值计算方法, 研究Kerr介质腔中处于Bell态的两个全同二能级纠缠原子与双模纠缠相干光场相互作用系统的原子布居数演化特性. 讨论了双原子体系的初态、 初始光场的平均光子数、 双模纠缠相干光场的纠缠程度及Kerr介质与双模光场的耦合强度对原子布居时间演化特性的影响. 结果表明, 当双原子体系的初态为|β₁₁〉时, 原子布居均不随时间变化; 当双原子体系的初态为|β₀₀〉,|β₀₁〉或|β₁₀〉且初始平均光子数达到一定值时, 演化特性呈现周期性的崩塌-回复效应, 并随初始光子数的增加, 其演化曲线的振荡频率增大, 振幅减小; 双模纠缠相干光场的纠缠程度不影响Rabi振荡频率, 但对振幅影响显著; Kerr介质与光场耦合系数达到一定值时, 对Rabi振荡频率和幅度及原子布居的崩塌-回复周期产生强烈影响. 

Evolution of Atomic Population in System of Two-mode Entangled Coherent Field Interacting with Atoms in Bell States in Kerr Medium

The time evolution of atomic population of the system, where the two identical two-level atoms in Bell states interact with two-mode entangled coherent field in a cavity filled with the Kerr medium, was investigatedby means of quantum theory and numerical method. The effects of the atomic initial state, mean photon numbers of field, the degree of the entanglement for the entangled coherent field, and the coupling strength between the Kerr medium and field on the atom’s population are discussed via numerical calculations. The results show that the atomic population is time-independent provided that the atoms are in |β₁₁〉 state. For the other three Bell states, there will appear the periodical collapse revival of atomic populationif the initial mean photon number reaches some special values. With the increase of the initial mean photon number, the oscillation frequency of the time-evolution of atomic population increases correspondingly, and the amplitude decreases. The degree of the entanglement of the two-mode entangled coherent field has no