CdS_xSe_(1-x)玻璃条型波导光双稳全开关动力学特性的研究

本文采用光纤端面耦合技术,在入射功率为6mW的情况下,观测到掺CdS_xSe_(1-x)半导体微晶玻璃条型波导中上升和下降时间分别为20和30ps的光学双稳跳跃过程,并从实验数据估算出CdS_xSe_(1-x)玻璃的三阶非线性系数x~((3))为1×10~(-9)esu,快速的光学双     

生物无机化学中若干重要基础理论问题的激光光谱研究

生物无机化学中若干重要基础理论问题的激光光谱研究周建英，李润华，周达君，彭文基，佘卫龙（中山大学超快速激光光谱学国家重点实验室，广州，５１０２７５）孟建新，计亮年，杨燕生（中山大学化学系，广州，５１０２７５）本项目由国家科委攀登计划“飞秒脉冲技术与越...     

STUDIES ON THE DYNAMICS OF OPTICAL BISTABILITY SWITCHING IN THE INTERNAL FABRY-PEROT CAVITY WITH A CdSxSe1-x-DOPED GLASS CHANNEL WAVEGUIDE

We report the optical bistability in CdS_xSe_1-x-doped glass channel waveguide with rise and fall times of about 24 and 30ps, respectively, in bistable switching by means of fiber coupling input with a power of about 3mW. The third-order nonlinear susceptibility (x⁽³⁾) of CdS_xSe_1-x-doped glass is estimated experimentally to be 1.8×10^-9 esu. The high speed switching and the value of x⁽¹⁾ show that the optical bistability is caused by an optical nonlinearity which can be attributed to the band-filling effect.     

TIME DECAY BEHAVIOR OF FULLERENE-C60 STUDIED BY TIME-RESOLVED PHOTOLUMINESCENCE

The time-resoved photoluminescence spectra of C₆₀ have been studied from toluence solution at room temperature and from thin film at both room temperature and 77K. A photoluminescence peak at about 730nm was detected from solution at room temperature and film at 77K, in which lifetimes waz determined to be 1.1 and 0.9ns, respectively. At room temperature, the photoluminescence peak of thin film shifted to 740 nm with fast decay behavior which was fitted well to a double-exponential lifetimes with τ₁ = 0.087ns, τ₂= 0.68 ns. Two relaxation mechanisms are given tentatively in explaining this phenomenon.     

InGaAs/GaAs单量子阱的瞬态光荧光特性(英文)

We used the time-resolved equipment consisting of a streak camera and normal photoluminescence set-up to measure the transcient behavior of the PL from the InGaAs/GaAs single quantum well sample, and thus obtained both the temporal resolution and the spectral resolution of the photoluminescence. A rapid decay of PL signal from the GaAs layer and the slow PL decay from the InGaAs well have beed found. From the experimetal results, the trapping efficiency of the carriers by the well is estimated to be about 80%.     

飞秒激光脉冲二阶干涉自相关法测量及其精细结构研究

本文用二阶相干自相关法测量飞秒激光脉冲宽度，测量过程完全由计算机控制和完成，测量精度达０．３飞秒。并分析了测量曲线的精细结构，发现其精细结构主要是由基频光相干场的振动频率所决定。     

A STUDY ON THE ULTRASONIC VELOCITY AND ATTENU-ATION IN NdFeB MAGNET WITHIN THE TEMPERATURE RANGE OF 80-300K(Ⅰ)

The ultrasonic velocity V and attenuation A of both longitudinal and shear waves in an anisotropic NdFeB magnet were measured over the temperature range from 80K to 300K by the pulse echo method. The anisotropy of the ultrasonic wave propagating in a NdFeB magnet was observed. Anomalous changes in both V-T and A-T curves in the temperature range of 110-160K were found, which might be due to the spin reorientation phase transition of Nd₂Fe₁₄B.     

超短脉冲激光测量的标定方法

在研究总结现有超短激光脉冲测量方法的基础上，对皮秒激光脉冲的测量及飞秒激光脉冲自相关二次谐波(SHG)的测量方法进行了统一的校正。实验中，利用迈克尔逊干涉光路的相对光程差，产生已知时间间隔，作为时间基准对皮秒、飞秒激光脉冲的测量进行了标定。     

采用532nm锁模激光研究量子阱中的带填充效应

采用532nm锁模脉冲激光和时间分辨测量系统测量了InGaAs/GaAa单量子阱在77K时,不同激发功率下的时间分辨光致发光谱.结果表明,在低激发功率时,阱中的发光峰的位置随时间变化不大.而在175mW激发时,发光峰在刚激发时就向短波移动10meV以上,然后随时间向长波移动.结果明确显示了存在于阱中的带填充效应.