超短光脉冲作用下的二能级原子

考虑到光场的振幅随时间分布的影响时,我们重新研究了光场与二能级原子相互作用的跃迁几率问题。在强光信号作用下,经过一定的数学代换后,上能级几率的求解可归结为类希尔方程求解;在弱光信号作用下,利用转动波近似(RWA),给出了二能级原子跃迁几率的解析表达式,并讨论了几种典型脉冲光场的分布。     

优质GaAs/Si和AlGaAs/Si材料的MOCVD生长研究

用自制常压MOCVD装置,在Si衬底上生长GaAs和AlGaAs外延层,在高温去除Si衬底表面氧化膜之后,采用两步法,即低温生长过渡层,再提高温度生长外延层。得到了表面镜面光亮的优质GaAs和AlGaAs外延层。X射线双晶衍射仪测试GaAs外延层,其回摆曲线半峰宽是200孤秒,GaAs和AlGaAs外延层在77K温度下,PL谱半峰宽分别是17meV和24meV。     

Hg(II)酉己合物与N2H4定向反应的研究

本文研究了Hg< I )配合物与N2H4的定向反应,得出该反应为定量四电子反应.该反应随反应体系pH值增大,反应速度加快.. Cu( I)是该反应有效的催化剂.文中讨论了该反应的反应机理,N,H:是该反应主要中间体,通过在反应液中加入不饱和酸已成功地截获N2H4     

东方钝绥螨空间分布型及抽样技术的研究

应用扩散型指标,Taylor幂法则和lwao m——x回归分析法,分析了东方钝绥螨在柑桔园的分布型。结果表明,东方钝绥螨在柑桔园呈聚集分布。其最适抽样数N=7.34+31.357 5 x1/2,利用该螨释放防治叶螨的序贯抽样的上下限T0（N）=4.2276N±6.3663 N1/2 .     

多模玻色二次多项式型系统的特性函数和准概率分布函数

运用多模玻色系统广义线性量子变换的普遍理论，对多模玻色二次多项式型系统进行了研究.给出了多模玻色二次多项式型系统的正规、反正规、Wigner特性函数、P表示和Q表示.举例讨论了该系统的压缩性质. 关键词： 多模玻色二次多项式型系统 特性函数 准概率分布函数     

Cavity phase matching via an optical parametric oscillator consisting of a dielectric nonlinear crystal sheet

We experimentally demonstrate cavity phase matching for the first time using a sheet optical parametric oscillator which is made of an x-cut KTiOPO(4) crystal sheet. This microcavity presents 220 kW peak power capability for near-frequency-degenerate parametric outputs with up to 23.8% slope efficiency. It also features unique spectral characteristics such as single-longitudinal-mode and narrow linewidth. These attractive properties predict broad applications of such a mini-device, such as terahertz generation, photonic integration, spectroscopy, and quantum information, etc.     

Multi-color display and its model for a white OLED combined with optical color filters

A bright white organic light-emitting diode (OLED) has been successfully fabricated in which a greenish-white emitting host Bis-(2-(2-hydroxyphenyl) benzothiazole)zinc (Zn(BTZ)₂) is doped with an orange-red fluorescent dye 5,6,11,12-tetraphenylnaphthacene (rubrene). The pure white light emission with CIE coordinates of (0.341, 0.334) is achieved at the driving voltage of 20 V, and the corresponding luminance and external quantum efficiency are 4000 Cd/m² and 0.63%. On the other hand, the pure red, green, and blue (RGB) emissions are obtained from the white OLED combined well with RGB custom-built optical color filters (CFs) with peaks at 616, 556, and 456 nm, respectively. Moreover, based upon the color mixture principles, we build a model of multi-color display mixed by the pure RGB emissions under the controllable bias.     

The circular and elliptic white-light dark spatial solitons in a photovoltaic self-defocusing nonlinear medium

We observed circular white-light dark spatial solitons in photovoltaic self-defocusing LiNbO₃:Fe crystal using an ordinary incandescent lamp as light source (a line source) with the filament of the bulb parallel to the crystalline c axis. Besides the above condition, the formation of the elliptic soliton needs an additive condition that the crystalline c axis is parallel to the minor axis of dark elliptic spot.