School of Physics, University of Melbourne, Parkville, Vic, 3010 Australia.
Phys Rev Lett. 2010 May 21;104(20):206601. doi: 10.1103/PhysRevLett.104.206601. Epub 2010 May 20.
We present a method for determining inelastic mean free paths (IMFPs) in materials using high-accuracy measurements of x-ray absorption fine structure (XAFS). For electron energies below 100 eV, theoretical predictions have large variability and alternate measurement techniques exhibit significant uncertainties. In this regime, the short IMFP makes photoelectrons ideal for structural determination of surfaces and nanostructures, and measurements are valuable for studies of diverse fields such as low-energy electron diffraction and ballistic electron emission microscopy. Our approach, here applied to solid copper, is unique and exhibits enhanced sensitivity at electron energies below 100 eV. Furthermore, it is readily applicable to any material for which sufficiently high accuracy XAFS data can be obtained.
我们提出了一种使用高精度 X 射线吸收精细结构（XAFS）测量来确定材料非弹性平均自由程（IMFPs）的方法。对于低于 100 eV 的电子能量，理论预测具有很大的可变性，并且替代测量技术表现出显著的不确定性。在这个能区，短 IMFPs 使得光电子非常适合表面和纳米结构的结构确定，并且测量对于诸如低能电子衍射和弹道电子发射显微镜等各种领域的研究具有重要价值。我们的方法，这里应用于固体铜，是独特的，并且在低于 100 eV 的电子能量下表现出增强的灵敏度。此外，它可以很容易地应用于任何可以获得足够高精度 XAFS 数据的材料。
