AMO Seminar: Robert Zillich 'Spectroscopy in Helium Nanodroplets'
Info about event
Matrix spectroscopy has the advantage that the atoms or molecules being probed can be isolated and cooled, but the matrix holding the "sample"
usually has a significant effect on the spectra. These effects can be minimized by using superfluid helium-4 as matrix. Therefore, spectroscopy of helium-4 nanodroplets doped with single atoms or molecules or clusters of them has become a versatile experimental tool.
Interpretation of spectra obtained in this quantum matrix require knowledge about the influence of helium on the dynamics of the probed atom or molecule. In my presentation, I will give an overview of calculation methods for this non-trivial quantum many-body system, based on Monte Carlo simulations, but also on traditional many-body techniques. I present some results on rotational spectra of neutral and ionic molecules inside and on the surface of helium clusters, and on the formation of alkali-helium exciplexes, and discuss the influence of superfluidity of helium on molecule rotation spectra. Experiments of large organic molecules and of metal clusters in helium-4 have gotten much less attention from the theoretical physics and chemistry community since accurate interactions potential are not known in this case. We are tackling this problem with a phenomenological approach to obtain the all-important interactions between the dopant and the He atoms.
Coffee/tea and cake will be served from 15:05