内禀退相干下Tavis-Cummings模型中原子的纠缠演化与贝尔不等式破坏

Entanglement evolution and Bell inequality violation of two atoms in Tavis-Cummings model withintrinsic decoherence

通过求解系统的Milburn方程,研究了两个二能级原子和单模场相互作用系统中原子间纠缠和贝尔不等式破坏随时间的演化特性,讨论了偶极相互作用、场与原子的失谐量对纠缠度以及贝尔不等式破坏的影响.结果表明:原子间偶极-偶极相互作用对纠缠度和贝尔不等式破坏有显著影响,失谐量增大会使两原子的纠缠度和贝尔不等式破坏变大,并且两原子所能达到稳定的纠缠受偶极相互作用系数与失谐量两者之差的影响.同时还发现两原子的纠缠与贝尔不等式破坏并不是单调的函数关系,很小的纠缠也可以产生贝尔不等式破坏.

Considering the interaction between two two-level atoms and a single-model field, we find an exact solution of the Milbum equation for the system. We investigate the time evolution of the entanglement between the two atoms and the maximal violation of Bell-CHSH inequality. The influence of dipole-dipole interaction and detuning between the caving and the atom on the entanglement and Bell violation is discussed. The effect of dipole-dipole interaction between two atoms on the entanglement and Bell inequality violation is obvious; with the detuning increasing, the entanglement between two atoms and Bell inequality violation becomes larger and we find that the stationary value of the entanglement between two atoms only depends on the difference between the dipole-dipole coupling intensity and the detuning. The Bell inequality violation and the entanglement does not satisfy the monotonic relation, a large Bell inequality violation may correspond to a small amount of entanglement.