非线性囚禁离子振动模式互关联函数的研究

为了研究非线性对囚禁离子沿两个正交方向的振动模式之间的互相关函数的影响,采用理论分析和数值计算相结合的方法,对单个2维三能级囚禁离子与两个经典驻波激光相互作用的非线性双光子Jaynes-Cummings模型进行了严格求解,并对囚禁离子沿两个正交方向的振动模式之间的互相关函数进行了数值分析。结果表明,当初始平均量子数较小时,反关联效应随Lamb-Dicke参量的增大先是增强然后减弱,但是关联效应却随Lamb-Dicke参量的增大一直增强。随着初始平均量子数的增大,反关联效应会减弱直至消失;表征非线性效应的Lamb-Dicke参量和初始振动运动平均量子数对交叉关联有明显的影响。

Study on cross correlation function of vibrational modes of nonlinear trapped ions

In order to study the influence of nonlinear parameters on the cross-correlation function of two vibrational modes of the trapped ions along mutually orthogonal directions, the exact solution of the nonlinear double-photon Jaynes-Cummings model which describes the interaction between a single two-dimension three-level trapped ion and two classical standing wave lasers was obtained by theoretical analysis and numerical computation. The cross-correlation function of two vibrational modes of the trapped ion was analyzed numerically. The results show that the anticorrelation effect is strengthened at first and then weakened with the increasing of the Lamb-Dicke parameters when initial average quantum number is small. But the correlated effect is always strengthened with the increase of the Lamb-Dicke parameters. The anticorrelation effect will be weakened and then disappear with the increasing of initial average quantum number. The initial average quantum number and Lamb-Dicke parameters characterized by nonlinear effects have obvious influence on cross correlation.