无周期光学超晶格中误差函数研究（英文）  

Research on the Relative Tolerance Function in Non-periodic Optical Superlattice

作　　者：张丽娟[1] 赵丽明[2] 

机构地区：[1]晋中学院信息技术与工程学院,山西晋中030600 [2]首都师范大学物理系理论物理中心,北京100048

出　　处：《光子学报》2017年第4期219-224,共6页Acta Photonica Sinica

基　　金：The National Natural Science Foundation of China(Nos.11274233,11004139);the Natural Science Foundation of Beijing(No.1102012)

摘　　要：利用非线性共轭梯度算法设计了无周期光学超晶格结构,研究了文献[12]提出的误差函数在该结构中的适用性.研究结果表明:误差函数能够很好地适用于无周期光学超晶格结构,且该结构比文献[12]中所用的非周期光学超晶格更具有一般性;当u′_2(x_n)和n保持很好的线性关系时,无周期光学超晶格结构中计算所得的误差函数曲线与文献[12]中的误差函数曲线几乎是重合的,说明了在无周期光学超晶格中达到了很好的准相位匹配.通过在样品中引入随机误差进一步研究了相位失配情况下误差函数在无周期光学超晶格结构中的适用性,结果表明:相位失配时无周期光学超晶格结构中计算所得的误差函数曲线与标准曲线是有偏离的,且相位失配程度越大,偏离也越大;对于一些误差函数曲线与标准曲线偏离不大的情况,误差函数仍可近似地用来估计无泵浦损耗近似的适用范围.The Non-periodic Optical Superlattice （NOS） structure was designed by using the the Nonlinear Conjugate-Gradient（NCG） algorithm, and the applicability in the NOS structure of the relative tolerance function mentioned in Ref. [12] was studied. The results show that, this relative tolerance function can apply to the NOS structure well, and the NOS structure is more general to compare with the Aperiodic Optical Super-lattice（AOS） which is used in Ref. [12]. When u2 （xm） and n keep a good linear relationship, the relative tolerance function curve calculated in the NOS structure is nearly coincident with that mentioned in Ref. [12], which shows that a Quasi-Phase-Matching（QPM） is well satisfied in the NOS structure. The applicability in the NOS structure of the relative tolerance function which is under the case of phase mismatching was also furtherly investigated by introducing the random error in the sample. The results show that, the relative tolerance function curve calculated in the NOS structure is not coincident with the standard curve under the case of phase mismatching, and as the mismatching degree increases, the relative tolerance function curves exhibit a larger deviation from the standard one. The applicable scope of Un-depleted Pump Approximation （UPA） can be approximately calculated by using the relative tolerance function when this deviation is not large.

关 键 词：二次谐波产生 误差函数 非线性共轭梯度算法 无周期光学超晶格 准相位匹配 

分 类 号：O437[机械工程—光学工程]