软X射线-真空紫外波段光谱光源研究

介绍长春光学精密机械与物理研究所进行的软X射线-真空紫外波段光谱光源研究工作。研制成功的壁稳氩弧光源光谱辐射稳定性和重复性达±0.3%,可作标准辐射源,用于真空紫外波段仪器光谱强度绝对辐射定标。研制成功的潘宁(Penning)光源、双等离子体光源和空心阴极光源,可以覆盖从十几个nm至几十nm波段范围,光谱辐射稳定性和重复性达±1.0%,提供不同工作气体在该波段的原子和离子线谱,用于光谱仪器的波长定标。所研制的激光等离子体光源,尤其是近期研制成功的无污染微液滴喷射靶激光等离子体光源,可以提供较高亮度的软X射线辐射,13.0 nm处激光-软X射线转换效率达0.75%／2π·sr／2%带宽,适合于光刻和该波段辐射计量研究。     

真空紫外双等离子体光源的研究

本文描述我们研制的真空紫外双等离子体光源的设计、结构及工作原理,讨论真空紫外性能测试,给出光源的真空紫外辐射特性测试结果。     

高分辨率傅里叶变换光谱技术在短波段光学中的应用及进展

讨论了傅里叶变换光谱技术向短波段光学扩展的必要性和主要技术难点,分别介绍了几种应用于紫外、真空紫外及软Ｘ射线波段的傅里叶变换光谱仪结构性能与原理,并进一步阐述了高分辨率傅里叶变换光谱仪在短波段光学中的应用     

高分辨傅里叶变换光谱技术在短波段光学中的应用及进展

讨论了傅里叶变换光谱技术向短波段光学扩展的必要性和主要技术难点,分别介绍了几种于紫外,真空紫外及软Ｘ射线波段的傅里叶变换光谱仪结构性能与原理,并进一步阐述了高分辨率傅里叶变换光谱仪在短波段光学中的应用。     

两种紫外-真空紫外光谱辐射标准的比对

研究了紫外 真空紫外波段壁稳氩弧光谱辐射标准光源及基于同步辐射标准的传递标准光源———氘灯的光谱辐射特性 ,建立了高精度光谱辐射计量系统 ,在 16 5～ 30 0nm之间 ,将两种类型光谱辐射标准进行比对 ,相对光谱分布的一致性好于± 5 %。     

大气遥感远紫外光谱仪绝对光谱辐照度响应度定标方法研究

主要针对可应用于空间高层大气遥感的远紫外光谱仪的光谱辐照度响应度定标方法进行研究。针对远紫外波段光谱测试标准装置少,实验系统所需真空度高,实验稳定性难以维持,传统漫反射板和积分球辐亮度定标方法在远紫外波段局限性大、难以利用等特点,研究了适用于远紫外光谱仪器的光谱辐照度绝对辐射定标方法,搭建了相应的真空实验系统,以一台远紫外光谱仪原理样机为对象对研究方法进行了实验验证。实验系统以标准氘灯、真空紫外单色仪和准直系统组成照射系统,将出射准直光辐照度用标准探测器进行标定,三者共同组成了标准光谱辐照度光源;利用该光源照射原理样机并读出相应信号,最终获得光谱辐照度响应度,从而实现了利用标准探测器进行照度传递的远紫外光谱仪器绝对光谱辐射定标,有效的进行了仪器定标。该方法定标不确定度约为7.7%,对远紫外波段空间高层大气遥感光谱仪的地面辐射定标研究具有重要意义。     

合肥光源的衍射光栅制备技术

正衍射光栅是合肥光源光束线中重要的分光元件。本文介绍伴随合肥光源而发展起来的衍射光学元件精密加工实验室衍射光栅制备技术及相关工作进展。一、引言合肥同步辐射装置是工作在真空紫外-软X射线波段的连续光源。在真空紫外-软X射线波段通常使用光栅单色器分光,将所需的单色光从同步辐射光源中分离出来。衍射光栅是合肥光源重要的色散元件。国家同步辐射实验室成立了光学组,并逐步发展成现在的衍射光学元件精密加工实验室,     

165—350nm同步辐射与壁稳氩弧光谱分布的比对

以合肥８００ＭｅＶ电子储存环同步辐射和壁稳氩弧作为初级标准光源，在１６５－３５０ｎｍ波段，标定了石英窗口氙灯的光谱分布，最大偏差为１１％，以石英窗口氘灯为传递标准光源，在紫外及真空紫外辐射区完成了同步辐射和壁稳氩弧两种基准之间的对比。     

远紫外像增强器光谱响应特性研究

利用星载光学仪器对极光在远紫外波段进行形态探测是研究沉降粒子能量等空间环境参数的重要手段,而远紫外像增强器是进行空间极光远紫外形态探测仪器中所必不可少的光电成像器件,其性能的优劣将直接影响整个仪器的工作情况,其中光谱响应特性是像增强器的重要的特性之一。采用同步辐射真空紫外波段光作为光源,利用光电倍增管和硅光二极管分别测量同步辐射和像增强器光强,我们对研制的远紫外像增强器在135～250 nm波段范围进行了光谱响应测试,测试结果表明该器件在140～190 nm范围内有较好的响应,响应峰值在160 nm左右,符合远紫外极光成像探测的应用要求。     

氟化氩离子准分子真空紫外辐射

利用激光等离子体软Ｘ射线为激励源，首次观察到离子性氟化氩准分子在１２５ｎｍ附近的真空紫外辐射，其实验结果与理论计算值符合很好。     

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.     

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.     

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.     

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.     

Theoretical analysis and simulation of conjugate heights for dual-conjugate AO system in lidar

A multi-conjugate adaptive optics （MCAO） can offer a possibility of widening field of view （FOV） characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle＇s expressions of two deformable mirrors （DMs） MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.     

Quick single-photon detector with many avalanche photo diodes working on the time division

Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.     

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.