为了在差频过程中得到较高的转换效率, 利用铌酸锂晶体的电光效应来改变晶体的折射率, 进而在非线性过程中调整位相失配量来实现差频转换效率的调制, 模拟了外加电场对差频转换效率的影响。结果表明, 利用铌酸锂晶体的电光效应, 可以在任意给定抽运光强的情况下, 获得较高的差频转换效率。这一结果对于获得新的中红外光源是非常有益的。

It is always expected that the conversion efficiency is as high as possible for nonlinear interaction at any pump intensity. A method was presented to control the conversion efficiency of difference-frequency generation (DFG) in the periodic poled lithium niobate, by modulating the refractive index induced by electro-optic effect. The variation of DFG conversion effieciency with the external electric field was simulated. The calculated results indicate that this method is feasible and very efficient in attaining the high conversion efficiency at any given pump intensity. This result is very useful to get new lasers especially in mid-infrared region.