The evolution of enhanced four-wave mixing based on Raman coherence as the probe intensity increases is observed experimentally in an ${^{85}{\rm Rb}}$ atomic vapor system. We propose that for a Doppler-broadened $\Lambda$-type level system, the generated anti-Stokes field from one-photon resonance will be suppressed by the dressed-states resonance and can be controlled by the probe intensity, which influences the effective transverse relaxation rate of Raman coherence. When the probe field is not so weak, the double resonance for dressed states will greatly suppress the anti-Stokes emission at the central frequency, and the signal peak will be split. We show that this phenomenon is a result of the destructive polarization interference between atoms with different velocities from the two types of resonance. Based on our model, we present a new, to the best of our knowledge, interpretation of four-wave mixing enhancement in the conventional $\Lambda$-type electromagnetically induced transparency system.

中文翻译：

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通过控制多层原子系统中的拉曼相干性来实现四波混合的演变

在$ {^ {85} {\ rm Rb}} $原子蒸气系统中，实验观察到随着探针强度的增加，基于拉曼相干性增强的四波混频的演变。我们建议对于多普勒加宽的$ \ Lambda $-型能级系统，由单光子共振产生的反斯托克斯场将被修整态共振所抑制，并可以通过探针强度来控制，这会影响拉曼相干的有效横向弛豫速率。当探查磁场不是很弱时，处于修整状态的双共振将极大地抑制中心频率处的反斯托克斯发射，并且信号峰值将被分裂。我们表明，这种现象是两种类型共振产生的具有不同速度的原子之间的破坏性极化干涉的结果。根据我们的模型，据我们所知，我们提出了一种新的解释，解释了传统的\\ Lambda $型电磁感应透明系统中的四波混频增强。