简并四波混频中的能级交叉效应

LEVEL CROSSING EFFECT IN DEGENERATE FOUR-WAVE MIXING

我们用微扰方法计算了近简并准二能级系统的三阶非线性极化率x^(3)(-ω;ω,ω,-ω)。研究了简并四波混频的能级交叉效应,并与共振荧光的能级交叉效应比较。指出简并四波混频的能级交叉效应可用来测量上能级及下能级的弛豫速率。

Third-order nonlinear susceptibility x(3) (-ω; ω,ω, -ω) is calculated in nearly-degenerate quasi-two-level system by perturbation method. We have studied the level crossing effect in degenerate four-wave mixing and compared it with the level crossing effect in resonance fluorescence. The possibility of using level crossing effect in degenerate four-wave mixing to measure the relaxation rate of upper and lower state is pointed out.