染料掺杂聚合物分散胆甾相液晶薄膜激光特性研究

采用激光染料DCM、向列相液晶TEB30A、手性剂S-811、聚乙烯醇(PVA), 通过微胶囊法制备了聚合物分散胆甾相液晶薄膜, 测量激光辐射谱, 研究了其激光辐射机理和温度调谐特性. 利用正交偏光显微镜观察器件织构, 看到液晶微滴分散均匀, 尺寸较大, 约为80 μm, 并且微滴中液晶分子呈现平面态排列织构. 以532 nm的Nd:YAG固体激光器作为抽运源, 测得在634.5 nm和680.2 nm波长处出现了尖锐的激光辐射峰, 线宽分别约为0.25 nm, 0.29 nm. 并与染料掺杂胆甾相液晶激光器件进行比较. 升高器件温度, 其输出激光波长蓝移, 获得666.7 nm至643.9 nm共22.8 nm的调谐范围. 由实验结果分析得出, 激光辐射机理为光子禁带末端激光, 出射波长分别对应光子禁带的两个边沿.     

基于Alq:DCJTI薄膜的光泵浦650nm微腔激光

设计研制了以分布式布拉格反射镜为腔镜、以主客体掺杂的红光发光材料Alq:DCJTI为增益介质的有机微腔结构。通过传输矩阵法对腔内驻波光场进行了模拟, 确定了合理的微腔结构。在紫外脉冲激光的泵浦下研究了微腔的激光性能。该微腔激光器的输出波长位于650nm, 观察到了明显的激光现象, 其中阈值强度约为110W·cm^-2, 阈值前后的FWHM从4.7nm窄化到3.2nm。     

平面金属等离激元美特材料对光学Tamm态及相关激射行为的增强作用

本文对具有类EIR色散特性的平面金属等离激元美特材料(planar plasmonic metamaterials, PPM)对光学Tamm态及相关激射行为的增强作用进行了研究. 我们首先运用传输矩阵方法分析了利用PPM结构的色散来增强光学Tamm态对应模式电磁局域密度的可能性. 其次, 我们将具有类EIR特性的PPM与一维光子晶体(photonic crystal, PC)合在一起设计了一种平面等离激元美特材料-光子晶体(PPM-PC)异质结构. 研究发现, 通过在电磁局域密度最高的PPM结构中(或附近)加入增益介质, 可观察到比通常光学Tamm态更强的激射增强效应及更明显的单色性响应. 这些特性使得这种PPM-PC结构有望被应用于低阈值激光器、荧光增强等方面.     

Two—photon Up—conversion Luminescent Properties of HMASPS and HEASPS in Three Different Polymer Matrices

Three dye-doped polymer rods in different matrices were synthesized in which wcak hydrogen bond, strong hydrogen bond and covalent bond existed between the dye and the polymer chain. And the two-photon up-conversion luminescent properties of HMASPS and HEASPS in three different microenvironments were studied.     

咔唑类化合物的光谱特性与三光子激射

测量了一系列新合成的咔唑类化合物的光谱特性。光谱研究结果发现端基团的选择引起双光子吸收截面的巨大变化。用1.3 μm强fs激光激发其中一双光子吸收截面高达617.3 GM的分子溶液,其波长和时间分辨光谱特性表明此分子的高方向性光发射是三光子诱导激射。[1 GM(Gppert-Mayer)=10-50 cm4·s·(photon)-1]。     

一种新型聚合物激光染料

报道了一种新型聚合物染料的受激发射特性     

激光混沌同步和解码以及优化

进行了激光混沌模拟信号(0.1—10GHz)和数字信号(0.2和0.3Gbit/s)以及频率键控调制解调等研究，优化分析了调制信号的频率和幅度等对同步误差和解调的影响以及激光器混沌键控速率极限；分析了彻底同步和伪同步，并优化分析了系统参数失配、反馈系数对同步误差以及同步时间的影响. 关键词： 激光 混沌 同步 解码 优化     

Phase control in an open Λ-type system with spontaneously generated coherence

This paper investigates the control role of the relative phase between the probe and driving fields on the gain, dispersion and populations in an open A system with spontaneously generated coherence （SGC）. It shows that by adjusting the value of the relative phase, a change from lasing with inversion to lasing without inversion can be realized; the values and frequency spectrum regions of the inversionless gain and dispersion can be obviously varied; high refractive index with zero absorption and electromagnetically induced transparency can be achieved. It is also found that when the driving field is resonant, the shapes of the dispersion and the gain curves versus the probe detuning are very similar if the relative phase of the dispersion lags π/2 than that of the gain, however for the off-resonant driving field the similarity will disappear; the gain, dispersion and populations are periodical functions of the relative phase, the modulation period is always 2π; the contribution of SGC to the inversionless gain and dispersion is much larger than that of the dynamically induced coherence.     

New Series of Dyes for Flashlamp-Excited Lasers

A new series of laser compounds which are derivatives of 7H-benzo[4, 5]imidazo[1, 2-c]chromeno[3, 2–e]pyrimidine have been developed and their working characteristics are presented. It is shown that the new compounds fluoresce with a high quantum yield (0.83–0.97) in the green spectral region; their methanol solutions gave effective lasing upon flashlamp excitation with a pulse duration of about 2.0 sec at the level 0.5. In a nonselective cavity they emit laser radiation in the range 540–570 nm. The influence of the molecular structure of the investigated dyes on their fluorescence and laser characteristics is discussed.     

铜蒸气激光器计算机辅助设计

 在已有的各种输出功率、激励条件参数和实际模拟程序基础上,对铜蒸气激光器计算机辅助设计进行改进,获得了适合于宽广参数条件下的模拟程序及实用曲线组。可在一定的激光输出功率条件下确定器件的激活体积;当口径选定后,可得铜蒸气激光器对应的电功率输入密度、激励电场、最佳重复频率和放电管壁温度值。