(Paper published: 2024.07.22)
In a new paper published in The Journal of Chemical Physics, Hylleraas members Simon Elias Schrader, Håkon Emil Kristiansen, Thomas Bondo Pedersen, and Simen Kvaal present a highly adaptive computational method for solving the time-dependent Schrödinger equation of a hydrogenic electron exposed to strong laser fields.
Electronic and nuclear quantum dynamics driven by attosecond laser pulses are highly challenging to simulate, not least because ionization and dissociation processes are omnipresent. Having recently demonstrated that Gaussian wave packets provide a compact and accurate basis for simulating such processes – see www.mn.uio.no/hylleraas/english/news-and-events/news/2024/paper-published-gaussians – this paper shows that linear combinations of Gaussians can be propagated in a numerically stable manner using Rothe’s method, which was developed almost a century ago for solving partial differential equations. In particular, it is demonstrated that relatively few Gaussian wave packets are needed to accurately reproduce high-harmonic-generation spectra of the hydrogen atom.
The paper can be downloaded at the JCP website or in preprint format at arXiv.