New paper on harmonic generation with RMT.

Last updated May 30, 2017 by Andrew Brown

The second published paper of PhD student, Ola Hassouneh, marks a genuine landmark in the research of the intense-field members of CTAMOP. The RMT method, the latest incarnation of time-dependent R-matrix theory, has previously been applied only to relatively short-wavelength (<390nm) laser-atom interaction. While this is fairly typical of an ab-initio method, it is rather unsatisfactory from an experimental perspective, as state-of-the art techniques in ultrafast physics typically employ lasers in the micron-wavelength regime. Previously this was thought intractable from a computational standpoint, as in such long wavelength fields, electrons can absorb many hundreds of photons, gaining extremely high angular momenta, and travelling very far from the nucleus. While it was thought that RMT may eventually be able to describe wavelengths on the order of 800nm, Ola jumped ahead of her supervisors and started running calculations at 1800nm!

In particular, Ola was investigating high-harmonic generation (HHG) from krypton and xenon atoms, and the paper presents these results alongside experimental data from the group of Andrew Shiner in Ottawa, Canada. Such a favourable comparison with experiment was a little unexpected, given that the code models a single atom in a `clean’ laser pulse, but the results show that the RMT code is now extremely well placed to lead the field of computational laser-atom physics in the coming years. So watch this space for more collaborations with experimental groups!

Link to the original paper


We are a Research Cluster of the School of Mathematics and Physics at Queen’s University Belfast in Northern Ireland. Our research interests are focused primarily on computational and theoretical physics.

Old Physics Building

The Old Physics Building,
where CTAMOP is situated.