Angular resolved low loss EELS
FNS funded project. Start 09/2008.
This project deals with the accurate determination of angular resolved low energy electron energy loss spectrometry. The scattering cross section of fast electrons passing through matter is related to the dielectric function of the investigated material. The energy range which can be analyzed is extraordinary, ranging from the infrared (< 1eV) to the hard X-Ray (2-3000 eV) region. In contrast to optical absorption, EELS is not limited to momentum transfer q = 0, thus giving access to an additional dimension of the loss function.
The aim of the project is to set up a reliable experimental and numerical technique to retrieve the momentum transfer resolved single scattering distribution and dielectric function at very low energy and with good accuracy and resolution. To compare the experimental result with ab initio calculations within the time dependent density functional theory and Bethe-Salpeter equation, and to use both theoretical calculations and experimental results to calculate the lifetime of hot electrons.