Electron Coincidence Spectroscopy
Our group works in the field of electron spectroscopy and scattering, with a focus on low energy electrons. We study energy dissipation processes as well as the transport and the emission of low energy electrons (LEEs) near solid surfaces, a topic of paramount importance for various fields: electron beam techniques, accelerator physics, space technology, nanolithography, irradiation of biomaterials with ionising radiation and attosecond physics to name but a few. LEEs are not only important for nanoscale analysis (microscopy, attosecond physics) but also act as agents inducing physico-chemical processes such as in electron lithography, electron beam induced deposition, astrochemistry and, last but not least, DNA-bond breaking induced by high energy ionising radiation striking biological tissue. The above topics all involve the many-body response of the solid state electrons to external perturbations which we study using spectroscopy with correlated electron pairs (coincidence electron spectroscopy).
Our present research activities comprise:
- Development of the NIST Database for the Simulation of Electron Spectra for Surface Analysis (SESSA)
- Development of an artificial intelligence (AI) tool for quantitative interpretation of XP-spectra in the framework of the EUSpecLab Marie-Curie project funded by the European union
- Measurement of optical and electronic properties via electron scattering experiments (dielectric function, electron affinity, band gap, inner potential)
- Electron coincidence spectroscopy (i.e. spectroscopy with correlated electron pairs) for detailed understanding the mechanisms at work at secondary electron emission from:
- 2D Materials (graphite, graphene, MoS2)
- Insulating surfaces (PMMA, PTFE, SiO2...)
- Simple metals (Al, Cu, Ag)
- Soft matter, DNA
- Special emphasis is put on the role of plasmon decay and the influence of the initial and final state electronic structure
- Study of many body processes using time resolved photo- and secondary electron spectroscopy (in collaboration with the Institute for Photonics, E387)