中文摘要：

Yb^＋3具有简单的二能级结构，利用双光子驱动建立起原子的相干，由于Yb^＋3的能级具有上下多重态的结构特点，使原子跃迁在多个Stark子能级间发生．这些跃迁的相干叠加决定着介质的非线性吸收和色散，而相干叠加的结果取决于驱动场的拉比频率．结果表明通过改变驱动场的拉比频率，可有效控制系统的双稳与多稳的存在与否和阈值强度的高低．

英文摘要：

The two-photon-driven can be used to build up the atomic coherence since the Yb^＋3 has the simple two-level structure. Atomic transitions can： take place in many Stark sublevels because of the characteristics of its energy level with up-and-down muhi-state structure. The coherent overlap of these atomic transitions can determine the nonlinear absorption and dispersion in the medium and the results of the coherent overlap depend on the Rabbi frequency of driving field. The results show that by changing the Rabbi frequency of driving field, we can effectively control the existence of bi-stable or multi-stable system and threshold level of intensity.