Time Resolved Electron Energy Loss Spectrometer

参照Siegbahn提出的X射线光电子能谱色散补偿原理，设计了一台EELS谱仪。在这种情况下，（1）原则上，进入单色器的所有电流都可以用于EELS测量，以及（2）通过能量高，因此，样品电流高。异能是光行差和空间电荷。在180 °半球光谱仪的情况下，焦点在180 °半球的边缘处，并且对于待定位的样品，在单色仪的输出和样品之间以及样品和分析仪的输入之间需要不丢失关于位置的信息的透镜。在这项研究中，90度扇形被用于光谱仪。通过多支电子枪的设计，实现了能量分辨率和透射率的优化。获得的能量分辨率为20 meV，相应的探测器电流为200 pA，这些结果为今后设计180 μ s球的时间分辨谱仪提供了重要信息。

An EELS spectrometer was designed by reffering to the dispersion compensation principle used by Siegbahn for X ray photoelectron spectroscopy. In this case, (1) in principle, all currents which enter the monochromater can be used for EELS measurements, and (2) pass energy is high, and thus, the sample current is high. Troubles are aberration and space charges. In the case of 180ﾟ semispherical spectrometer, the focus is at the egde of the 180ﾟ sphere and for the sample to be positioned, lenses which do not lose information on positions are needed between the output of the monochrometer and the sample and between the sample and the input of the analyzer. In this study, the 90ﾟ sector was used for the spectrometer. The optimization of the energy resolution and transmission was performed by the design of several electron guns. The obtained energy resolution was 20 meV,and the corresponding detector current was 200pA.These results are expected to give important informations on the future design of a time-resolved spectrometer by the use of 180ﾟ sphere.