title: Laser induced amplified spontaneous emission from the f 0(g)(+) (3P0) ion-pair state of I2.
abstract: Laser induced amplified spontaneous emission (ASE) from the f 0g (+) ((3)P0) (vf = 1-7) ion-pair state of I2 was directly observed using an optical-optical double resonance technique with the B 0u (+) (vB = 21) valence state as the intermediate state. The emission detected at ~1660 nm was assigned to transitions from the f 0g (+) state to the D 0u (+) ((3)P2) ion-pair state. The transitions observed in the dispersed IR emission spectra were found to be between vibrational levels having the same vibrational quantum numbers in both electronic states, vf = vD. This is due to the almost parallel nature of the potential energy functions of the f 0g (+) and D 0u (+) states, leading to almost unit values for the Franck-Condon factors for vf = vD. That the observed infrared emission is due to ASE is shown by the facts that it propagated in a limited range of solid angles, exhibited a clear threshold against the input-laser power, and had different polarization to that of laser induced fluorescence.
authors.affiliation: Graduate School of Chemical Science and Technology, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan.
authors.forename: Shoma
authors.initials: S
authors.lastname: Hoshino
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Araki
authors.forename: Hiroki
authors.initials: H
authors.lastname: Furukawa
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Ross
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsukiyama