Monte Carlo Simulation of Growth of Thin Film Prepared by Pulsed Laser

We use the Monte Carlo simulation method to perform the early growth stage of thin film prepared by pulsed laser deposition.We focus on the number of point defects on the substrate surface varying with the energy density of laser and substrate temperature.The results shows that the laser energy and the substrate temperature strongly affect the morphology and size of the growth islands and the deposition rate of thin film,Our results are in good agreement with the related experimental results.     

光盘阵列系统的一种性能优化方法

提出了一种用低性能驱动器组建高性能光盘阵列系统性能的优化方法。针对传统的低性能光盘驱动器(驱动器内部数据传输率及接口速率均较低),提出了一种新型的数据传输模式。采用此优化方法可以使光盘阵列系统的整体性能得到较大地提高。同时还可以提高系统整体的性价比。     

激光对远距离运动目标的辐照性能研究

研究激光对远距离运动目标的辐照功率在激光通信、激光破坏等领域具有重要意义。一般估算辐照功率时常忽略目标的随机运动。在考虑目标的随机运动概率密度分布的基础上,建立了远距离运动目标的精确激光辐照功率模型,并与辐照静止目标时的情形进行了定量的分析比较。辐照运动目标等效于扩大的激光束辐照静止目标。当系统的瞄准方差小于由模型计算出的等效静止方差极限时,可将目标看作为静止状态,由此带来的辐照功率估算误差小于10%,否则在计算时必须考虑目标的运动状态。     

End-pumped Nd:YAG zigzag slab laser with weak pump absorption

A diode-pumped Nd：YAG oscillator laser with an end-pumped zigzag slab architecture and weak pump absorption is developed. An output power of 253 W with a slope efficiency of 50.2% and an optical-optical conversion efficiency of 39.6% is achieved from the resonator, which emits the maximum power of 290 W with 840-W pump power. An optimum laser diode （LD） array coolant temperature is chosen in an attempt to realize the weak but uniform pump absorption. of zigzag slab resonator depends sensitively on the Furthermore, we have confirmed that the performance incident angle of the beam at the slab end face.     

多纵模激光F-P标准具双边缘测风可行性分析

讨论采用多纵模激光器作探测光源用于双边缘多普勒激光雷达测风的可行性。给出了多纵模激光器谐振腔腔长与边缘滤波器F-P标准具腔长之间的关系。分析了多纵模双边缘测风的主要特性,计算灵敏度、信噪比和径向测速误差,并与单纵模测风性能进行对比。可用类似单纵模测风中动态频率跟踪技术解决多纵模激光器频率漂移问题。     

基于多分辨率融合距离的低质量星系光谱红移测量方法

星系光谱红移测量是大规模天体光谱巡天项目中的一个重要研究内容,其目的是从在光谱中测量出对应星系由于多普勒效应引起的红移。随着银河系外巡天项目的开展,观测目标距离(红移)越来越远,其星等越来越暗,光谱的质量也随之越来越差,如何能够有效准确地从这些低质量的光谱测量出红移是河外巡天面临的一个重要问题。基于此问题,充分考虑到低质量星系光谱的特点及数据特征,新定义了一种针对低质量巡天光谱数据的多分辨率融合距离,以此为基础提出一种针对低质量星系光谱的红移测量方法。该方法充分结合不同分辨率下光谱的特征,计算距离时首先将模板光谱和待测光谱同时降到多个相同分辨率下,该分辨率下所有波长采样点都计算一个偏差进而得到一个距离,然后将多个分辨率下得到的距离通过加权得到一个融合距离。基于多分辨率融合距离提出的星系红移测量方法,能够有效的解决低质量星系光谱的红移无法准确测量的问题。研究了不同信噪比下红移测量的精度,在信噪比大于5之后,该方法测量准确率可以达到90%以上。大量实验表明,提出的方法在星系光谱质量较低的情况可以非常准确地从中测量出红移,测量误差和红移大小无关,可以很好地应用于大规模巡天数据的星系光谱红移测量中。     

Efficient corner-pumped Nd:YAG/YAG composite slab laser

A corner-pumped type is a new pumping type in the diode-pumped all-solid-state lasers, which has the advantages of high pump efficiency and favourable pump uniformity. A highly efficient corner-pumped Nd:YAG/YAG composite slab laser is demonstrated in this paper. The maximal continuous-wave output power of the 1064~nm laser is up to 18.57~W with a slope efficiency and an optical-to-optical conversion efficiency of 44.9{\%} and 39.8{\%}, respectively. Inserting an acousto-optic $Q$-switch in the cavity, the highest average output power of the quasi-continuous wave 1064~nm laser of 6.73~W is obtained at a repetition rate of 9.26~kHz. The experimental results show that a corner-pumped type is a kind of feasible schedules in the design of diode-pumped all-solid-state lasers with low or medium output powers.     

基于微观IBM对电子—核散射及核电磁性质的研究——（Ⅰ）BE理论方案

从价核子自由度出发构造出核跃迁电荷／电流密度算符,采用Dyson玻色子展开技术给出了获取核玻色子形式跃迁电荷／电流密度有效算符的一种微观方法（BE方法）。利用微观相互作用玻色子模型（IBM）提供的波函数可在玻色子态空间中求出核跃迁电荷／电流密度,结合电子－核散射以及核电磁跃迁的形式理论,建立了可研究电子－核散射各种形状因子,微分散射截面以及核约化跃迁几率、电磁多极矩、核态g因子等物理量的理论方案,在一种微观sdIBM-2框架下,结合现有理论方案,初步计算^192Os核的能谱、ES跃迁皮色子结构函数（BSF）以及21^＋态到01^＋态的跃迁电荷密度(TCD）,理论结果能够对上述物理量作出较合理的描述。     

高激发态钠原了与分子碰撞能量转移及分子扩散带辐射的增强效应研究

在钠原子－分子混合体系中,实验研究了加入缓冲气体对高位态原子－分子碰撞能量转移和分子扩散带辐射的增强效应;运用瞬态碰撞模型作了理论计算,理论结果与实验结果相符合。     

High—Dimensional Integrable Models with Infinitely Dimensional Virasoro—Type Symmetry Algebra

Using every realization of the Virasoro-type symmetry algebra[σ(f1),σ(f2)]=σ(f1f2-f2f1),we can obtain various high-dimensional integrable models under the meaning that they possess infinitely many symmetries,By means of a concrete realization ,many(3 1)-dimensional equations which possess Kac-Moody-Virasoro-type infinite dimensional symmetry algebras are obtained.