The RMT method for many-electron atomic systems in intense short-pulse laser light

Abstract

We describe a new ab initio method for solving the time-dependent Schrödinger equation for multi-electron atomic systems exposed to intense short-pulse laser light. We call the method the R-matrix with time-dependence (RMT) method. Our starting point is a finite-difference numerical integrator (HELIUM), which has proved successful at describing few-electron atoms and atomic ions in strong laser fields with high accuracy. By exploiting the R-matrix division-of-space concept, we bring together a numerical method most appropriate to the multi-electron finite inner region (R-matrix basis set) and a different numerical method most appropriate to the one-electron outer region (finite difference). In order to exploit massively parallel supercomputers efficiently, we time-propagate the wavefunction in both regions by employing Arnoldi methods, originally developed for HELIUM.

Keywords:

• multi-electron
• R-matrix
• finite-difference
• strong laser fields
• high performance computing

Acknowledgements

MAL and JSP acknowledge funding under the HECToR distributed CSE programme, which is provided through The Numerical Algorithms Group (NAG) Ltd. LRM, HWvdH and KTT acknowledge funding from the UK Engineering and Physical Sciences Research Council. LAAN acknowledges funding from the Science Foundation Ireland Stokes Lectureship Programme. We also acknowledge support from the European Science Foundation COST Action CM0702.