【摘要】 通过向SiO2Opal模板中填充钛酸乙酯制备TiO2光子晶体,观测到光子晶体带隙位置的移动达62nm,并发现光子晶体的有序度随填充率的升高而下降.向聚苯乙烯Opal模板中填充钛酸乙酯,制备成当时填充率最高、带隙最短的紫外波段TiO2反Opal光子晶体(中心波长~380nm),并根据测量的其透射谱估算出其填充率约为12%,即Opal模板孔隙的50%被填充.本文还对二维PPLN光子晶体进行了研究.建立了一套高压极化装置和电压数据采集装置,通过外加电场极化法成功制备出了具有正方形和矩形两种晶格形状二维PPLN光子晶体.利用二维PPLN的二阶准相位匹配,测量了其对1.064μm激光的二次谐波转换效率,并研究了晶体的温度、激光的入射角度及占空比对二次谐波转换效率的影响.利用矩形晶格实现了多方向、多波长倍频高效输出.更多还原

【Abstract】 In this paper,we report some results on inverse opal photonic crystal and two-dimensional periodically poled lithium niobate photonic crystal.First, the process of infiltrating TiO₂ into SiO₂ Opal was systematically studied. Because of the infiltration of TiO₂,the gap of SiO₂ Opal was shifted to longer wavelength and a maximum shift of 62nm was observed.Furthermore,an inverse TiO₂ Opal with larger filling fraction,～12%,was fabricated,whose band gap in the Γ-L direction is located in the ultraviolet region（～380nm）.Then two-dimensional nonlinear photonic crystals of lithium niobate with uniform square lattices were fabricated by applying external electric fields.The variations of second-harmonic output with crystal temperatures,incident angles and reversed duty cycles were measured.Red,yellow,green,blue,and violet coherent radiations were generated in the nonlinear photonic crystal with rectangular lattice in the collinearly and non-collinearly quasi-phase matching geometries.The results showed that two-dimensional nonlinear photonic crystal could be used to generate various colors simultaneously and efficiently in different directions.更多还原