Fabrication and characterization of a PbTe quantum dots multilayer structure

Multilayer PbTe quantum dots (QDs) and SiO₂ were grown by pulsed laser deposition (PLD) and Plasma enhanced chemical vapor deposition (PECVD) techniques. The crystalline structure, QD size and size dispersion were observed by high-resolution transmission electron microscopy (HRTEM) measurements. This technique allows one to grow PbTe QDs as small as 1.8 nm diameter and 0.6 nm size dispersion. The whole structure can be used in a Fabry–Perot cavity for an optical device operating at the mid-infrared region.     

单光子态的产生与测量

报道了通过自发参量下转换产生单光子态的实验研究,使用中心波长425 nm的飞秒脉冲泵浦Ⅰ类非共线相位匹配的BBO晶体,在实验上得到单光子计数率为2.978×10-4,并分析了实验中的相关问题.     

半导体激光器发射光谱实验仪

设计了一种半导体激光器发射光谱实验仪 ,可以用来观测LD发射的荧光光谱、激光光谱 ,以及了解光栅外腔选取单纵模、压窄线宽、波长调谐的机理 .该实验仪结构紧凑 ,物理概念清晰 ,适用于大专院校的光学实验教学     

全光纤脉冲压缩器的理论及实验研究

对色散位移光纤＋普通单模光纤构成的全光纤脉冲压缩器进行了理论分析，分析了压 缩效果与光纤参数及输入脉冲参数的关系；对不同中心波长和脉宽的主动锁模光纤激光器的 输出脉冲进行了压缩实验，均得到了近变换限Sech的压缩脉冲，实验结果与理论分析一致. 关键词： 全光纤脉冲压缩器 压缩因子 基座能量 主动谐波锁模光纤 激光器     

Role of Bulk Vaporization in the Dynamics of Laser-Induced Erosion Plumes of Metals

In different regimes of exposure of metals to pulsed laser radiation, we show the role played by the liquid-drop phase formed from the target material in a laser-induced erosion plume due to bulk vaporization, in the dynamics of this plume. For some metals, the ranges of power densities of the acting laser radiation, at which the condensed-phase particles influence the passage of laser radiation to the target surface, have been determined experimentally. The mechanism of realization of a low-threshold breakdown has been revealed.     

机载海洋激光测深系统参量设计与最大探测深度能力分析

详细讨论了机载海洋激光测深系统最大测量深度与相关因子之间的关系，并利用最小可探测信噪比为判据，对机载海洋激光测深系统在白天和晚上工作进行了数值模拟，通过比较最大测量深度与激光脉冲峰值功率、接收视场角、接收口径和光谱接收带宽等关系，确定了系统的主要参量。以确定的参量建立的系统具有白天49m和晚上65m的最大测深能力，可完全满足在沿岸带以及岛礁的测量要求。     

大口径光束波前采样器(孔栅)的研制

应用平面波角谱理论，分析了采样器对光波场采样和分光的基本原理以及对空间采样频率的选择规则，描述了实际研制的大口径采样器的结构设计，并通过数值方法和高能激光大气传输实验研究了高能激光经采样器前／后的远场光斑分布关系。结果表明：利用光束波前采样器能高保真地实现对高能激光束的分光。     

Two-Frequency Brillouin Fiber Laser Based on Bragg Grating Fabry-Perot Cavity

A novel and simple two-frequency Brillouin fiber laser is presented. It is based on a fiber Fabry-Perot cavity with fiber Bragg gratings as reflectors. The model of stimulated Brillouin scattering in fiber grating-based Fabry-Perot resonator is investigated. The laser allows conversion efficiency of close to 100% and suppresses the higher-order Stokes waves. The theoretical prediction is presented and the experimental demonstration is realized.     

高能、超短脉冲、可调谐激光器用掺镱氟磷酸盐玻璃研究进展

Yb^3 与其它稀土离子相比有最简单的能级结构，这使它具有一些独特的性质，如避免激发态吸收，消除上转换和浓度猝灭等，因此它是高能输出激光器介质的理想掺杂离子。氟磷玻璃综合了氟化物玻璃和磷酸盐玻璃的优点，可降低磷酸盐的声子能量，改善其易吸湿性；提高氟化物玻璃的物理化学性能等，这使它成为稀土掺杂可调谐光纤激光器的很好的掺杂介质。众多研究表明，Yb^3 掺杂氟磷玻璃是一种很有前途的激光工作物质。本文总结了Yb^3 掺杂氟磷玻璃的特点，性质，结构及存在的问题。