Photoelectron-photoion coincidence spectroscopy of ethanol in two-color intense laser fields

Itakura, Ryuji; Ikuta, Tomoya*; Hosaka, Koichi*; Yokoyama, Atsushi; Yamanouchi, Kaoru*; Kannari, Fumihiko*

Photoionization dynamics of ethanol in two-color (400 and 800 nm) intense laser fields is investigated using photoelectron-photoion coincidence spectroscopy. It is found that the fragment ion CHOH is formed dominantly through the ionization to the electronically excited state by the 400-nm pulse when a 400-nm pulse and a 800-nm pulse are temporally separated. When a 400-nm pulse is temporally overlapped with a 800-nm pulse, the ionization to the electronically excited state by the 400-nm pulse is significantly suppressed, indicating that the ionization channel to the electronically excited state is closed due to the AC stark up-shift by the 800-nm pulse.