超微半导体AgBr的量子尺寸效应

本文研究了间接带半导体ＡｇＢｒ由于空间尺寸的限制产生的吸收，荧光兰移，激子振子强度增强的量子尺寸效应，观察到旋－轨道分裂带至导带的２８４ｎｍ吸收峰，经硫处理的Ａｇｂｒ直接激子吸收峰从３１０ｎｍ移至３０１ｎｍ。相应的荧光从３４０ｎｍ移至３２４ｎｍ，同时在８５０ｎｍ处产生了一新的荧光带。     

Synchronizability of Highly Clustered Scale-Free Networks

We consider the effect of clustering coefficient on the synchronizability of coupled oscillators located on scale-free networks. The analytic result for the value of clustering coefficient aiming at a highly clustered scale-free network model, the Holme-Kim model is obtained, and the relationship between network synchronizability and clustering coefficient is reported. The simulation results strongly suggest that the more clustered the network, the poorer the synchronizability.     

Analysis of Frequency Spectrum of Laser-Induced Vibration of Microbeam Resonators

The vibration phenomenon during pulsed laser heating of micro-beams is investigated. The beam is made of silicon and is heated by a laser pulse with a non-Gaussian temporal profile and with an ultrashort pulse duration of 2ps, which incites vibration due to the thermoelastic damping effect. This coupled thermoelastic problem is solved using an analytical-numerical technique based on the Laplace transformation. The damping ratio and resonant frequency shift ratio of beams due to the air damping effect and the thermoelastic damping effect are also examined and discussed.     

Adsorption of L-Alanine on Cu（111） Studied by Scanning Tunnelling Microscopy

The adsorption of L-alanine on Cu（111） surface is studied by means of scanning tunnelling microscopy under ultra-high vacuum conditions. The results show that the adsorbates are chemisorbed on the surface, and can form a two-dimensional gas phase, chain phase and solid phase, depending on deposition rate and amount. The adsorbed molecules can be imaged as individual protrusions and parallel chains in gas and chain phases respectively. It is also found that alanine can form （2 × 2） superstructure on Cu（111） and copper step facet to （110） directions in solid phase. On the basis of our scanning tunnelling microscopic images, a model is proposed for the Cu（111）（2 ×2）-alanine superstructure. In the model, we point out the close link between （110）-direction hydrogen bond chains with the same direction copper step faceting.     

考虑量子效应的Zakharov方程组的孤波解

借助Maple程序，利用扩展的双曲函数法和双函数法求解了考虑量子效应的Zakharov方程组，得到了多种孤波解，其中包括亮孤波解、W型孤波解、M型孤波解和奇性孤波解. 关键词： 量子效应 Zakharov方程组 扩展的双曲函数法 孤波解     

退压式La_3Ga_5SiO_(14)晶体电光调QNd∶YAG激光器激光性能研究

通过对硅酸镓镧(LGS)晶体旋光性与电光效应的交互作用的理论研究,推导出晶体旋光性和电光效应共同作用下的光强表示式I=1-4B2(Asin 2ω-Ccos 2ω)2。利用此表示式设计计算了旋光晶体LGS尺寸为8 mm×8 mm×25 mm电光Q开关在1064 nm波长使用时的开关电压和偏振角分别为4995 V和27.3°。将理论研究得到的结论应用于LGS晶体电光调Q的Nd∶YAG晶体激光器的实验研究中,实验结果与理论计算结果基本一致。得到输出能量为361 mJ,脉冲宽度为7.8 ns的脉冲激光输出。     

快重离子辐照C60薄膜的强电子激发效应研究

利用能量为2.0GeV的¹³⁶Xe和2.7GeV的²³⁸U离子对C₆₀薄膜进行了辐照,并用傅立叶变换红外光谱、X射线衍射谱和拉曼散射技术分析了辐照过的C₆₀样品,在傅立叶变换红外光谱上,首次观察到一个位于670cm^－1处的,表征未知结构的新峰,研究了其强度随电子能损和辐照剂量的变化规律.分析结果表明,电子能量转移主导了C₆₀薄膜的损伤过程;而损伤的部分恢复是由强电子激发的退火效应引起的;另外,离子的速度在损伤的建立过程中也起了一定的作用     

Compression of Soliton Pairs in Dispersion-Decreasing Fibres

The compression of soliton pairs in fibres with decreasing dispersion is studied. The results show that generation of high-quality stable pedestal-free pulses is strongly affected by the interaction between soliton pairs. The initial phase difference between two solitons can modify soliton interaction and can make the neighbouring solitons never collide periodically. The soliton pairs can be compressed selectively so that one of the two solitons can achieve enhanced compression by controlling the initial phase difference.     

He光双电离末态波函数动量相关效应

在入射光子能量为79.6 eV～139 eV范围内,利用DS3C模型计算了不同碰撞几何条件下He光双电离的三重微分截面(TDCS),并与3C模型计算结果、CCC理论结果和实验数据做了比较.表明,末态波函数动量相关效应成功地修正了3C结果,特别当入射光子能量接近阈值时,明显改善了与实验结果的符合程度.