Strong electric-field effects on the structure profiles of doubly excited resonances in He ground-state photoionization

Abstract

Electric-field effects on the doubly excited resonant structures in He ground-state photoionization are investigated theoretically using the complex-rotation method with a B-spline-based configuration interaction basis. Angular-momentum states up to ${L}_{\mathrm{max}}=3$ are coupled together by the external electric field for the final states. The variations of the structure profiles for the ${M}_{L}=0$ components of He $(2,5a)$ and $(2,6a)$ ${}^{1}{P}^{o}$ and ${}^{1}{D}^{e}$ resonances for selected dc electric-field strengths are examined. The changes of the resonant energies and widths are also presented.