环境温度对多光子Jaynes-Cummings模型制备的原子与单模腔场纠缠态的影响

Temperature Effects on Thermal Entanglement in Multi-photon Jaynes-Cummings Model

借助于共生纠缠度方法 ,考察了共振的多光子Jaynes-Cummings模型的热纠缠态现象 .研究结果表明 :原子与单模腔场形成纠缠态的纠缠度随环境温度升高而急剧地减小 ,但在该Jaynes -Cummings模型中存在产生热纠缠态的临界温度 ,当环境温度超过这一温度值时 ,原子与腔场的纠缠态消失 .同时也表明 ,临界温度仅由原子与腔肠的耦合强度和原子跃迁时发射或吸收光子数决定 .因此 ,选择强耦合的原子与腔场量子系统可以在较高环境温度下实现原子与腔场的纠缠态并保持它 .

We investigate thermal entanglement produced by resonant mul ti -photon Jaynes-Cummings model by means of the concurrence. It is shown that the concurrence decreases with the increasing of temperature. There exists a critica l temperature, above which thermal entanglement of atom and field mode vanishes. The critical temperature increases with the increasing of the coupling constant and the absorbing or emitting photon numbers per atomic transition. Thermal ent anglement can be generated under high temperature for sufficiently strong coupli ng.