基于全息聚合物分散液晶的有机二维光子晶体激光器的研究

摘要

采用一次性曝光光路制备了基于全息聚合物分散液晶的亚微米周期染料掺杂二维光子晶体,晶格常数为582nm.选取4-（二氰亚甲基）-2-甲基-6-（4-二甲氨基苯乙烯基）-4H-吡喃作为激光染料,利用输出波长为532nm的Nd：YAG倍频脉冲激光器作为抽运光源对染料掺杂二维光子晶体进行抽运,得到了中心波长为627.4nm的窄线宽、低阈值的输出激光,激光线宽为0.4nm,阈值能量约为22.7μJ.与目前国外的报道相比,激光线宽和阈值能量都有了很大幅度的降低.将其与基于一维光栅的分布反馈式激光器相比,线宽从1.4n%In this paper,we report a kind of dye-doped two-dimensional photonic crystal based on holographic polymer dispersed liquid crystals （HPDLC） with a lattice constant of 582 nm,which is prepared conveniently with a single step holographic exposure.Under the excitation of a frequency-doubled Nd：yttrium-aluminum-garnet laser operating at a wavelength of 532 nm,optically pumped lasing with narrow bandwidth and low threshold is observed from a 4-（dicyanomethylene）-2-methyl-6-（4-dimethylaminostyryl）-4H-pyran dye-doped two-dimensional photonic crystal.The results show that the emitted lasing peak is centered at about 603 nm with a full width at half maximum of only 0.4 nm,and the threshold energy is about 22.7 μJ,which is evidently lower than the reported previously.The laser bandwidth decreases by a factor of three from 1.4 nm to 0.4 nm compared with that of the dye-doped HPDLC transmission grating.This result exhibits a bright prospect in application of tunable photonic crystal laser.