Modeling strong-field processes in (almost) real molecules

Serguei Patchkovskii
SIMS NRC
Department of Theory & Computation
100 Sussex Drive
Ottawa, ON K1A 0R6
Canada

Modeling of strong-field processes in many-electron systems presents a
formidable computational challenge. Ab initio treatments of such systems
have so far been limited to at most two electrons and/or low-dimensional
models. Larger problems of practical interest are usually treated with
model one-electron Hamiltonians. We have recently proposed a new
approach [1] for ab initio simulation of electron dynamics of molecules
in atoms in molecules. The technique is based on: a) use of
non-antisymmetric "proxy" wavefunction and b) expansion in the mixed N/(N-1)-
electron basis of the neutral molecule and (possibly several) ion states.
The effects of molecular potential on the continuum and correlations
between the bound and continuum electrons are treated, permitting realistic
simulations of electron dynamics in strong laser fields. We present some
initial results obtained with the new technique, including angular-resolved
ionization yields in strong fields and high-harmonic spectra of polyatomic
molecules.

[1] M. Spanner and S. Patchkovskii, Phys. Rev. A 80, 083411 (2009)