Ab-initio studies of few photon ionisation of helium

Tejaswi Katravulapally
2019 Journal of Physics, Conference Series  
In this work, an ab-initio method is used to study few-photon ionisation of helium with linearly and circularly polarized light.The photoionization cross sections are estimated from the ionization yields calculated by directly propagating the time-dependent Schrödinger equation (TDSE) and are compared with those obtained from the lowest-order (non-vanishing) perturbation theory (LOPT). The results show a clear deviation of the TDSE yields from those of the LOPT as well as the dominance of the
more » ... dominance of the linearly-polarized ionization yields over the circularly polarized ones, towards higher field intensities.
doi:10.1088/1742-6596/1289/1/012029 fatcat:frwpf7cbajgi7bej7ngwqa7uei