Giant above-threshold absorption by diatomic molecules in ultra-short strong pulses of resonant VUV lasers

The non-linear dynamics of electron excitation in diatomic molecules is studied for ultra-short laser pulse with λ=147 nm, τ=1 fs and peak intensities I=1013–1016 W/cm2. The electromagnetic wave frequency is in resonance to an electronic transition in the molecule. The molecule is modeled by a system of two active 1D electrons moving in the field of a frozen core. The time dependences of electron density distribution, electron energy, and one-electron/two-electron ionization probability are calculated and show the effect of giant above-threshold absorption in the pulse of intensity I∼1016 W/cm2.