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1.
PETRA II, a 12 GeV accelerator at DESY, Hamburg, is used to produce synchrotron radiation (SR) for experiments in the hard
X-ray regime when it is not running as injector for HERA. The beam from an undulator is split by a diamond crystal in Laue
geometry to feed two experimental stations, one of which is now dedicated for nuclear resonance experiments. The X-ray energy
may be chosen in the range from 5 to 55 keV covering all isotopes already observed with SR and many interesting candidates
for new resonances. Tuning may be performed by optimising the magnetic gap and the storage ring energy. In particular, the
opportunities for timing experiments are unique due to a very flexible filling mode of the storage ring. The flux at the sample
position is comparable to undulator beams at ESRF. The second beamline covers higher energies up to some 300 keV and may also
be used for nuclear resonance experiments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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V. N. Korchuganov N. Yu. Svechnikov N. V. Smolyakov S. I. Tomin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2010,4(6):891-897
Synchrotron radiation (SR) generated by homogeneous magnetic fields of bending magnets is now employed at the Siberia-2 electron
storage ring. It is planned that, in the near future, most of the storage ring’s free straight sections will be equipped with
insertion devices (undulators and wigglers). Two projects of specialized radiation sources based on the Siberia-2 stor age
ring are discussed. The first source is a vacuum milliundulator intended for generation of extremely bright X-ray beams. An
X-ray source with vertically limited diffraction is shown to be feasible when the vertical emittance of an electron beam is
equal to the diffraction emittance of photons with an energy of 2 keV. The second source uses edge radiation (ER) generated
at the ends of bending magnets of the storage ring. Calculations show that, in the infrared and ultraviolet spectral regions,
the ER intensity must exceed the intensity of standard SR formed by the homogeneous field of a bending magnet. 相似文献
4.
Super-resolution filters based on a Gaussian beam are proposed to reduce the focusing spot in optical data storage systems. Both of amplitude filters and pure-phase filters are designed respectively to gain the desired intensity distributions. Their performances are analysed and compared with those based on plane wave in detail. The energy utilizations are presented. The simulation results show that our designed super-resolution filters are favourable for use in optical data storage systems in terms of performance and energy utilization. 相似文献
5.
Solid immersion lenses (SIL) facilitate high numerical aperture (NA) and consequent sub-wavelength diffraction limited focusing in near-field optics based systems. Such systems are in commercial and research use for various applications including near-field scanning optical microscopy, ultra-high-density magneto-optic data storage and near-field nanolithography. Here, we present a novel manufacturing method using SIL-based near-field optics for laser-induced patterning on silicon wafers. The near-field effect of SILs was investigated by using hemispherical lenses made of three different materials (BK7, Sapphire, LaSFN9) to superfocus an incident Q-switched, 532 nm Nd:YAG laser beam transmitted through a focusing objective. This optical arrangement achieved a laser-processed feature resolution near the diffraction limit in air. Results of experiments that were conducted at various processing conditions to investigate the effects of varying incident laser power (with peak pulse power less than 1 W), pulse width, number of pulses and size of SIL on processed feature size and resolution are presented. Experimental results are compared with numerical simulations using the simplified model. 相似文献
6.
在科学技术新需求的推动下,同步辐射光源持续往前发展。目前,同步辐射装置发展已历经三代,正处于第四代同步辐射光源蓬勃发展阶段。基于衍射极限储存环的同步辐射装置是第四代同步辐射光源的典型代表之一。第四代同步辐射光源主要发展趋势是进一步减小电子束流发射度,使光源具有极好的横向相干性,以及产生圆截面辐射的能力。如果束流发射度降至光学衍射极限“辐射波长/4π”,其亮度比第三代同步辐射光源高2个数量级。这种同步辐射光源在性能上发生的质的飞跃,将给同步辐射实验技术带来实质性的突破,从而给前沿科学技术研究和现代产业发展带来全新的机遇。从国际同步辐射发展趋势入手,首先介绍低能区衍射限储存环光源的特色和性能,然后介绍其带来的同步辐射实验技术的进步,并浅析低能区衍射限储存环光源在材料科学、能源科学、生命科学和环境科学上的应用,以及其带来的产业机遇。最后,总结和展望了低能区衍射限储存环光源带来的技术突破和潜在的应用前景。 相似文献
7.
In low- and medium-energy storage rings for synchrotron radiation (SR) production, it is necessary to use high-performance insertion devices (IDs) in order to meet the increasing demand for high X-ray flux to perform life science and material science, since the maximum beam energy and beam current cannot be changed in storage rings without major rebuilds of the accelerator systems. 相似文献
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可用于光存储和光学信息处理的SrS(Eu,Sm)电子俘获薄膜的研究 总被引:3,自引:1,他引:2
报道用电子束蒸发法制备的SrS(Eu,Sm)电子俘获薄膜的特性,给出了这种薄膜的X射线衍射图、原子力显微镜(AFM)形貌观察结果、光谱及存储的图像照片等。结果表明所制备的电子俘获薄膜具有很好的光学特性,具有应用在光存储和光学信息处理上的能力。 相似文献
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I. Bukreeva A. Gerardino F. Perennes S. Cabrini A. Vicenzo 《Optics Communications》2006,259(1):366-372
A novel route for fabrication of compact optical system for X-rays is presented. It is based on the extensive use of tools developed for microelectronics and micromechanics: electron beam lithography, optical lithography and X-ray lithography. Virtually any shape can be obtained in order to match the system to the different needs. In this paper, we concentrate the attention on focusing system made by nested mirrors. A system for synchrotron radiation source and one for laboratory source have been designed and simulated by a ray-tracing code developed ad hoc. The main parameters and the fabrication tolerance errors have been evaluated. The first prototypes have been produced following different fabrication routes. They are presented here together with considerations for future developments. 相似文献
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The application of electron-beam lithography to the generation of diffractive optical elements topology is examined. The formula for the estimation of exposure data volume for variable-shaped electron-beam lithography is presented as a function of diffractive optical element parameters and approximation accuracy. A special software dedicated to preparing exposure data for fabrication of diffractive optical elements is developed. Diffractive optical elements with an artificial refractive index are manufactured with a feature size much less than the wavelength. Design and experimental results on photomasks fabrication for an optical element focusing radiation into a ring with pregiven parameters are presented. The photomask set is manufactured for a reflecting optical element focusing the high power CO2 laser beam into two points with required parameters for laser welding. 相似文献
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Systematical study of the trapping forces of optical tweezers formed by different types of optical ring beams 总被引:2,自引:0,他引:2
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The technique of optical tweezers has been improved a lot since its
invention, which extends the application fields of optical tweezers. Besides
the conventionally used Gaussian beams, different types of ring beams have also been
used to form optical tweezers for different purposes. The two typical
kinds of ring beams used in optical tweezers are the hollow Gaussian beam and
Laguerre--Gaussian (LG) beam. Both theoretical computation and experiments
have shown that the axial trapping force is improved for the ring beams
compared with the Gaussian beam, and hence the trapping stability is
improved, although the transverse trapping forces of ring beams are smaller
than that of Gaussian beam. However, no systematic study on the trapping
forces of ring beam has ever been discussed. In this article, we will investigate
the axial and transverse trapping forces of different types of ring beams
with different parameters systematically, by numerical computation in which
the ray optics model is adopted. The spherical aberration caused by the
refractive index mismatch between oil and water is also considered in the
article. The trapping forces for different objectives that obey the sine
condition and tangent condition are also compared with each other.
The result of systematical calculation will be useful for the applications
of optical tweezers formed by different types of ring beams. 相似文献
15.
研制了上海光源同步辐射空间干涉仪,用于储存环束团横向截面尺寸及发射度的精确测量。对干涉仪工艺设计中的光路参数、关键设备选型、数据处理方法及数据采集处理软件结构进行了分析讨论。结合束流实验完成了系统调试及运行参数优化,结果表明,CCD增益系数与曝光时间设置对测量精度有显著影响,增益系数设为0 dB,曝光时间设为200 ms时,随机测量误差可控制在μm量级。对上海光源储存环横向束斑尺寸进行了精确测量,结果表明:空间相干度曲线近似为高斯分布,可以采用单一空间频率的相干度测量值进行快速束斑尺寸计算;水平束斑尺寸实测值为52.4 μm,与理论值预期值53.0 μm相比,差异小于2%;系统测量误差约为5.5%,主要误差来源为相干度随机测量误差。 相似文献
16.
在文[1]讨论了电子束能量调制的前提下,讨论电子束在光速调管中色散段的密度调制,以及诸多因素对密度调制的影响。给出了色散段设计参数的选择原则,并讨论了电子束主要参数的限制。最后结合合肥同步辐射环的参数给出了一组储存环紫外波段自由电子激光中密度调制的参考数据。 相似文献
17.
ZHANG Chuang 《中国物理C(英文版)》2009,33(Z2)
This is a status report of the project on befalf of the BEPC Ⅱ team.BEPC Ⅱ is a major upgrade radiation(SR)source with its outer ring,or SR ring.As a collider,BEPC Ⅱ operates in the beam energy region of 1-2.3 GeV with design luminosity of 1×1033 cm-2s-1 at 1.89 GeV.As a light source.the SR ring operates at 2.5 GeV and 250 mA.Construction of the project started in the beginning of 2004.Installation of the storage ring components was completed in October 2007.Commissioning is in progress.There are still many issues for further studies before reach to 3×1032 cm-2s-1. 相似文献
18.
HIRFL-CSR主环电子冷却模拟计算 总被引:2,自引:0,他引:2
以16O8+为例,用电子冷却模拟程序计算了冷却时间随离子能量、初始发射度、初始动量分散、离子流强以及离子电荷态的变化规律,研究了储存环在冷却段的β函数和色散函数对冷却时间的影响. 相似文献
19.
The conceptual of Hefei Advanced Light Source, which is an advanced VUV and Soft X-ray source, was developed at NSRL of USTC. According to the synchrotron radiation user requirements and the trends of SR source development, some accelerator-based schemes were considered and compared; furthermore storage ring with ultra low emittance was adopted as the baseline scheme of HALS. To achieve ultra low emittance, some focusing structures were studied and optimized in the lattice design. Compromising of emittance, on-momentum and off-momentum dynamic aperture and ring scale, five bend acromat (FBA) was employed. In the preliminary design of HALS, the emittance was reduced to sub nm·rad, thus the radiation up to water window has full lateral coherence. The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders. The HALS should be one of the most advanced synchrotron radiation light sources in the world. 相似文献