在四能级N模型原子系统中, 当一束饱和光和一束探测光同向传播并且两束耦合光反向传播时, 由于饱和光与探测光不能处于相消多普勒状态, 可以同时在吸收光谱中观测到五个下凹, 均为相干光学烧孔。通过缀饰态理论, 计算了烧孔的位置, 发现中间深而窄的烧孔是由两个相干光学烧孔叠加而成。通过参考系数的合理调节以及改变饱和光的拉比频率, 可以改变烧孔形成的深度; 通过改变耦合光的拉比频率, 可以改变烧孔形成的位置。最后通过数值模拟得出饱和光的拉比频率在相干光学烧孔中实现光速减慢起到重要作用。这些结论对未来的光量子存储、光量子信息都有着重要的应用价值。

Five coherent hole-burning can be simultaneously observed in the absorption spectra of four-level N-style atoms vapors. In this system they adopt a saturated laser co-propagates and two coupling lasers counter-propagate with a probe laser, and the saturated laser can not be in the destructive Doppler state with the probe light. The positions of the coherent hole-burning can be explained by Dressed-state theory. The middle narrow deep hole-burning is induced by the superposition of two coherent hole-burnings. The depth of the coherent hole-burning can be changed by adjusting the reference parameters and the Rabi frequency of the saturated laser. The positions of the coherent hole-burning can be changed by modulating the Rabi frequency of the probe light. By numerical simulation it is found that Rabi frequency of the saturated light plays an important role in slowing the propagating speed. These results may be useful in optical quantum memory and optical quantum information.