Laser-induced electron diffraction in H₂ with linear and circular polarization ultrashort XUV laser pulses

Numerical solution of the time-dependent Schrödinger equation for a two-dimension model of H₂ ionization by intense ultrashort (few cycles) extreme ultraviolet (XUV) laser pulses are presented to compare linear and circular polarization angular distributions for aligned molecules. Both ground (X ¹Σ_g⁺) and excited (A ³Σ_u⁺) states ionization is calculated at equilibrium and for extended large internuclear distance configurations to study the effect of electron delocalization via molecular orbitals vs electron localization in Heitler-London atomic wave functions. It is found that at large distance for ionized electron wavelengths less than the internuclear distance, circular polarization ionization angular distributions exhibit signature of the entanglement of electrons by exchange, thus, allowing for a measure of exchange entanglement.