Selective bond breaking in dissociative ionization of ethanol induced by tailored intense laser fields

Itakura, Ryuji; Yamanouchi, Kaoru*; Kannari, Fumihiko*

It is demonstrated that the branching ratio between the C-C and C-O bond breaking processes in the dissociative ionization of ethanol is controlled by tailoring the intense laser pulse shape. Through systematic investigation of the dependence of the parameters of the laser pulses on the yield ratio between the two dissociation pathways, mechanisms of bifurcating into the two pathways are discussed. The important key factors for determining the yield ratio were found to be the pulse duration and wavelength. It was proposed that the nonadiabatic electronic excitation is efficiently induced by the wave packet evolution within the laser pulse duration.