铍原子1s22snp 3P态精细结构的理论计算

以多电子原子精细结构哈密顿的球张量形式为基础,借助不可约张量理论,对铍原子1s22snp(n=2-6) 3P态精细结构(包括自旋-轨道相互作用、自旋-其它轨道相互作用和自旋-自旋相互作用)进行了具体地计算,并将计算结果与文献结果进行了比较,符合地较好。同时,计算了1s22snp(n=2-6) 3P态精细结构参数A和B的值。     

类铍离子1s~22snp~3P(n=2～6,Z=5～8)态能级和精细结构参数的理论计算

在准相对论框架下,以多电子原子精细结构哈密顿的球张量形式为基础,借助不可约张量和角动量耦合理论,导出类铍离子1s22snp(n=2-6)3P态精细结构(包括自旋-轨道相互作用、自旋-其它轨道相互作用和自旋-自旋相互作用)和精细结构参数的解析表达式,并利用我们所开发的程序,对各项进行了具体地计算,计算结果与文献符合地较好.     

碳原子1s22s22pns 3P态精细结构的理论计算

提出了构造碳原子1s22s22pns 3P态波函数的新方法,以多电子原子精细结构哈密顿的球张量形式和不可约张量理论为基础,开发了一套计算碳原子1s22s22pns 3P态精细结构的Mathemtica程序,具体计算了碳原子1s22s22pns 3P(n=3-6)态的精细结构(包括自旋-轨道相互作用、自旋-其它轨道相互作用和自旋-自旋相互作用),计算结果与实验值非常接近。     

碳原子1s~22s~2pns~3P态精细结构的理论计算

提出了构造碳原子1s~22s~2pns~3P态波函数的新方法,以多电子原子精细结构哈密顿的球张量形式和不可约张量理论为基础,开发了一套计算碳原子1s~22s~2pns~3P态精细结构的Mathemtica程序,具体计算了碳原子1s~22s~22pns~3P(n=3～6)态的精细结构(包括自旋-轨道相互作用、自旋-其它轨道相互作用和自旋-自旋相互作用),计算结果与实验值非常接近.     

碳原子1s~22s~22pns~3P态精细结构的理论计算

提出了构造碳原子1s~22s~22pns ~3P态波函数的新方法,以多电子原子精细结构哈密顿的球张量形式和不可约张量理论为基础,开发了一套计算碳原子1s~22s~22pns ~3P态精细结构的Mathemtica程序,具体计算了碳原子1s~22s~22pns ~3P(n=3～6)态的精细结构(包括自旋-轨道相互作用、自旋-其它轨道相互作用和自旋-自旋相互作用),计算结果与实验值非常接近.     

氦原子自旋-其它轨道相互作用精细结构参数的理论计算

以多电子原子精细结构哈密顿的球张量形式和氦原子非相对论性能级结构理论为基础,借助不可约张量理论,建立了计算氦原子自旋-其它轨道相互作用精细结构参数的一种解析理论形式.完成了所有的角向积分和自旋求和计算,自旋-其它轨道相互作用精细结构参数最终用若干个径向积分来表示.以氦原子(1s2p)3P态为例,借用类氢形式的径向函数对这些径向积分进行了近似计算.计算结果表明:在氦原子的精细结构中,自旋-其它轨道相互作用与纯自旋-轨道相互作用的作用效果相反;在总自旋-轨道相互作用精细结构参数中,自旋-其它轨道相互作用起决定性作用,它决定着精细结构分裂的顺序.     

类碳体系基态能量的精细结构(英文)

以多电子原子精细结构哈密顿的球张量形式和不可约张量理论为基础,建立了计算多电子原子精细结构(包括自旋-轨道相互作用、自旋-其它轨道相互作用和自旋-自旋相互作用)能量的一般性解析理论形式,应用所建立的理论对类碳体系(Z=6～8)基态的精细结构能量进行了具体计算,计算结果与实验数据符合得较好.     

氦原子自旋-自旋相互作用精细结构参数的理论计

利用多电子原子的精细结构哈密顿算符的球张量形式,通过计算氦原子的自旋-自旋相互作用哈密顿算符在|LSJMJ〉表象中的矩阵元,导出了氦原子的自旋-自旋相互作用精细结构参数的理论计算式,并就氦原子(n1s)(n2p)组态具体计算参数B之值.     

类锂离子里德堡态中的自旋-其它轨道相互作用

以多电子原子精细结构哈密顿的球张量形式和三价原子的非相对论性能级结构理论为基础,借助不可约张量理论,建立了计算类锂离子里德堡态中的自旋-其它轨道相互作用能的一种解析理论形式.完成了所有的角向积分和自旋求和计算,自旋-其它轨道相互作用能最终用径向积分来表示.应用所建立的理论对类锂离子(1s2np)2Pj态的自旋-其它轨道相互作用能进行了具体分析.     

镁原子里德堡能级的计算

依据最弱受约束电子势模型理论,计算了镁原子1s22s22p63snp 3P2,1,0(n=3～50) 和1s22s22p63sns 3S1 (n=4～50)里德堡系列的能级和量子亏损. 计算结果与已有的33个实验数据符合得很好,预言了136个能级的位置.     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Hybrid Wavelength and Code Division Multiple Access in Optical Networks

A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.