Molecular frame angular distribution of tunnel ionization probability of HCl molecule determined by correlation measurement between electron and fragment ion

Akagi, Hiroshi; Staudte, A.*; Shiner, A.*; Turner, F.*; Villeneuve, D. M.*; Ivanov, M. Yu.*; Corkum, P. B.*

Angular dependence of tunnel ionization from a molecule in a strong laser field reflects the structure of the molecular orbital the electron tunnels from. Ours are the first measurements for a heteronuclear molecule. To determine the angle, we use circularly polarized light and detect the electron and fragment ion in coincidence. Concentrating on HCl, bond softening allows us to select the tunnel ionization from HOMO-1. The angular distribution is consistent with the shape of the orbital, modified by a contribution from the dipole moment of the neutral molecule and its cation.