论文标题
使用光电子光谱测量谐振非弹性X射线散射:计算研究
Using photoelectron spectroscopy to measure resonant inelastic X-ray scattering: A computational investigation
论文作者
论文摘要
共振非弹性X射线散射(RIX)已成为重要的科学工具。但是,传统的高分辨率RIX测量值(<100 MEV),尤其是在软X射线范围内,需要大型和低通量的光栅光谱仪,以限制测量精度和简单性。在这里,我们在计算上研究了一种测量RIX的不同方法的性能,用于分析X射线(PAX)的光电光谱法(PAX)。该方法将RIX的X射线测量问题转换为电子测量问题,从而可以使用紧凑的高通量电子光谱仪。在PAX中,要测量的X射线被入射在转换器材料上,并用电子光谱仪测量所得的光电子PAX光谱的能量分布。然后,通过一种利用机器学习概念的反卷积算法来估算事件X射线频谱。我们研究了一些示例PAX案例。将Ag的3D水平作为转换器材料,并使用10 $^5 $检测到的电子,我们准确地估计了模型rixs Spectrum中具有100秒MEV宽度的特征。使用尖锐的费米边缘编码RIXS光谱,我们准确区分了100 MeV FWHM峰,分别为45 MEV,其中检测到的10 $^7 $电子,这些电子从Fermi级别的0.4 eV之内进行了摄影。
Resonant inelastic X-ray scattering (RIXS) has become an important scientific tool. Nonetheless, conventional high-resolution RIXS measurements (<100 meV), especially in the soft x-ray range, require large and low-throughput grating spectrometers that limits measurement accuracy and simplicity. Here, we computationally investigate the performance of a different method for measuring RIXS, Photoelectron Spectrometry for Analysis of X-rays (PAX). This method transforms the X-ray measurement problem of RIXS to an electron measurement problem, enabling use of compact, high-throughput electron spectrometers. In PAX, X-rays to be measured are incident on a converter material and the energy distribution of the resultant photoelectrons, the PAX spectrum, is measured with an electron spectrometer. The incident X-ray spectrum is then estimated through a deconvolution algorithm that leverages concepts from machine learning. We investigate a few example PAX cases. Using the 3d levels of Ag as a converter material, and with 10$^5$ detected electrons, we accurately estimate features with 100s of meV width in a model RIXS spectrum. Using a sharp Fermi edge to encode RIXS spectra, we accurately distinguish 100 meV FWHM peaks separated by 45 meV with 10$^7$ electrons detected that were photoemitted from within 0.4 eV of the Fermi level.