MP-CITDSE: A set of ab-initio programs for the simulation of hydrogenic and helium-like atom-laser interactions

MP-CITDSE is a package of programs which solves the time-dependent Schrödinger equation for hydrogenic and helium-like atomic systems interacting with an ultra-short laser pulse (of attosecond or femtosecond duration). The output of the computations – with some minimal processing – may be used to calculate excited populations, single and double ionisation yields, kinetic, angular and radial electron distributions, and harmonic yields. For the Helium atom, a full account of the inter-electronic correlation effects is included via a configuration interaction approach; for the time propagation of the wavefunction a spectral basis expansion on the eigenstates of the field-free Hamiltonian is used; for this reason post-processing of the expansion coefficients just after the pulse lead to simple formulas for quantities of experimental interest.