【摘要】 用干涉法在LiNbO3:Fe晶体中写入光子晶格的过程中,发现有一维干涉条纹一分为二、二维干涉点阵一分为四的分裂现象.从数学上对这种分裂现象进行了定量描述,首先由入射光场得到写入光栅的透射率函数,然后由入射光场和透射率函数的乘积导出晶体的出射光强,根据出射光强的表达式分析了空间谐波的产生过程,证明了利用光折变效应可以构造倍频光子晶格.更多还原

【Abstract】 The phenomenon that one one-dimensional interference fringe splits into two and one two-dimensional interference fringe splits into four is found in fabricating photonic lattices in LiNbO3:Fe crystal using interference method.This kind of cleavage phenomenon can be described quantitatively by the mathematic theory.In this paper,we will first obtain the transmission coefficient of written grating by incidence light field,then deduce the expression of the effluent light intensity of the crystal by the product of incidence light field and transmission coefficient.Finally,we analyze the generated spacial harmonic by the expression of the effluent light intensity and prove that the spacial frequency-doubling photonic lattices can be constructed by photorefractive effect crystal.更多还原