Powder synthesis and spectroscopic properties of ytterbium-doped yttrium oxysulfide

Ytterbium-doped yttrium oxysulfide(Yb:Y2O2S)has been synthesized by solid-state reaction with sulfide flux.Diffuse reflection and emission spectra have been measured in order to determine the crystal field splitting of Yb3 ion in the YOS lattice.According to the crystal-field levels probed in the spectra,the crystal field splitting of 2F7/2 manifold of Yb3 ion in YOS is 709 cm-1,which is large enough for the quasi-three-level laser operation of Yb3 ion.Emission peak position,width,full-width at half maximum (FWHM),and normalized intensity of Yb:YOS are fitted from its emission spectrum.For comparison,relevant data of 5.4 at.-% Yb:YAG is also provided.     

对关联对核基态和集体激发态性质的影响

基于相对论平均场和BCS理论,研究了共振连续对奇特核对关联性质的影响. 利用S矩阵方法，通过设定合理的散射态边界条件来得到单粒子共振态的能量和宽度. 通过引入连续态能级密度的方法来处理共振态宽度对核对关联的贡献. 计算结果显示合理地处理共振态对对关联性质的贡献在研究滴线附近核性质时很重要. 它可以影响中子的对隙、费米能级、对关联能以及总结合能. 其次,基于RMF+BCS基态,采用线性响应理论给出了描述开壳核集体激发态性质的准粒子相对论无规位相近似理论. 并且将该方法应用于开壳核120Sn的各种同位旋标量集体激发态性质的研究中. 研究表明：对关联对核的集体激发性质的影响主要表现在低能集体激发态上,考虑对关联后的相对论无规位相近似理论能够很好地再现低能集体激发的实验结果.     

ψ(2S)扫描实验中衰变宽度误差与亮度的确定

结合ψ(2S)扫描实验中衰变宽度测量的特点,介绍了确定积分亮度的叠代方法与确定衰变宽度误差的抽样方法.这两种方法既简单又精确可靠     

各向异性Besov-Wiener类由多重样本的最优恢复

研究各向异性Besov-Wiener类SrpqθB（R^n）在Lq（R^n）,（1＜q≤P＜∞）中由其函数和它们的导数样本的最优恢复问题,确定了误差界的精确阶.     

Femtosecond first-order autocorrelation measurement based one-photon induced photocurrent in Si Schottky diodes

Si Schottky diodes promise to provide cheap, reliable, and linear detectors for use in femtosecond and picosecond pulse width measurement. At low pulse excitation density (<100 pJ/cm²), the pulse width can be deduced from the first-order autocorrelation, and the measured results are in agreement with the theoretical ones. When pulse excitation density is larger than 1 nJ/cm², the pulse trailing edge is distorted due to bandgap reduction in semiconductor Si and the pulse width cannot be measured accurately by means of the first-order autocorrelation. The interference fringes presented in the first-order autocorrelation measurement can provide a way of calibrating the delay, and the pulse width can also be obtained by calculating the number of interference fringes.     

光源谱线宽度对测量滤光片光谱分布影响的研究

从理论上分析光源的光谱宽度对滤光片测量结果的影响,给出光源光谱曲线及滤光片透过率曲线为正态分布时测得的滤光片光谱分布曲线.     

Single-particle resonance states of 122Zr in relativistic mean-field theory combined with real stabilization method

Single-particle resonance states of 122Zr are studied in the real stabilization method within the framework of relativistic mean field theory. Two efficient methods are adopted to extract the resonance energy and width of 122Zr. The results are compared with those obtained from the analytic continuation in the coupling approach and scattering phase-shift methods.     

低温时半导体PN结的物理特性及玻尔兹曼常数的测量

本文验证在１５０Ｋ—２００Ｋ低温下硅半导体载流子仍然严格符合玻尔兹曼分布率