Dissociative ionization of a large molecule studied by intense phase-controlled laser fields

Abstract

We report on the dissociative ionization of a large polyatomic molecule induced by quantum control of tunneling ionization. The directionally asymmetric tunneling ionization induced by phase-controlled two-color $(\ensuremath{\omega}+2\ensuremath{\omega})$ intense $(1.0\ifmmode\times\else\texttimes\fi{}{10}^{13}\phantom{\rule{0.3em}{0ex}}\mathrm{W}∕{\mathrm{cm}}^{2})$ laser fields with 130-fs pulses led to selective ionization of oriented molecules, which reflect the geometric nature of the highest occupied molecular orbital. We conclude that in the case of 1-iodohexane the molecular Ammosov-Delone-Krainov model for tunneling ionization is qualitatively valid even for the large polyatomic molecule, and that the nonadiabatic multielectron dynamics, which lead to fragmentation, play a much more important role in molecular cations than in neutral molecules.