三色场驱动和任意强度单色场探测三能级系统的非线性响应

讨论了三色驱动级联型三能级模型电磁诱导透明(EIT)现象。首先研究了级联型三能级模型在三色驱动场和单色探测场作用下原子的跃迁情况,据此写出了密度矩阵所满足的方程。通过数值求解,得到了探测场的吸收色散谱并对它进行了分析,发现了两个重要的结论:一个是三色驱动的吸收谱能通过驱动场的相位控制在探测场中心频率处产生透明窗口;另一个是改变驱动场的两个边频的拉比频率相对于中心频率的位相之差能够改变吸收色散曲线的形状。

Nonlinear Response of a Three-level System Driven by a Trichromatic Field and Probed by an Arbitrary Intense Monochromatic Field

In this paper,we discussed the electromagnetically induced transparency(EIT) in three-level system driven by a trichromatic field.Firstly,we studied the transitions in three-level system driven by a trichromatic field and probed by a monochromatic field.Based on that,we wrote out the density matrix equation.Then we solved the equations by the method of numerical calculation and drawing the absorption and dispersion spectra.Two characteristic features are found.One is that the central transparency can be made by controlling the phases of excitation components and the other is that we can get different lineshapes of absorption and dispersion spectra by changing the relative phases of two sideband excitation components to the central component.