利用电磁感应透明实现弱光场条件下的强非线性效应,开辟了一个崭新的非线性光学研究领域-“弱光非线性光学”。主要介绍了基于电磁感应透明的Kerr非线性和四波混频效应。Kerr非线性在全光学开关、全光学逻辑运算和光量子逻辑门等方面有着潜在的应用价值。四波混频也具有非常广泛的应用,其中最重要的是把可调谐相干光源的频率范围扩展到红外和紫外。在简并情况下,四波混频对于自适应光学中的波前再现是很有用的。另外,在材料研究中共振四波混频技术是强有力的光谱分析工具。
It is important to obtain strong nonlinearities under the conditions of weak-light through electromagnetically induced transparency (EIT),' which opens up a new field about optical nonlinearities, named as weak-light nonlinearity. Kerr nonlinearities and four-wave mixing based on electromagnetically induced transparency are introduced. Kerr nonlinearities may be used on the all-optical switches and all-optical logical arithmetic and optical quantum logical gate and so on. Four-wave mixing effects also have many ap- plications. The most important application is that it can expand the frequency of coherent light to infrared and ultraviolet spectrum. In the case of degeneration, four-wave mixing effects are useful for wavefront re- construction in the adaptive optics. Besides, in material research, the resonant four-wave mixing technique is a vigorous spectrum analyzing tool.