Datadocument_PRR2020

We provide results of the numerical integration of the one-dimensional Time-Dependent Schrödinger Equation (TDSE) of the helium atom in the interaction with a strong electromagnetic field. We compare different theoretical models: (i) Two Active Electrons (TAE), which is the exact 1D description of the He atom, (ii) Idle Electron model (IDL), considering two-electron correlation, and only one electron interacting with the external field, (iii) Single-Active Electron approximation (SAE), and (iv) the exact 1D description of the helium cation (He⁺).