We report the first detection of laser-induced amplified spontaneous emission (LIASE) between the F0u+(P03) and E0g+(P23) ion-pair states of Cl2. Strong UV emission belonging to the E0g+(P23) – B3Π(0u+) transition was observed upon excitation to single vibronic levels of the F0u+(P03) state. Only the vibrational levels of the E0g+(P23) state with a relatively large Franck-Condon overlap between the laser-prepared vibrational levels of the F0u+(P03) state were found to be generated. The intensity distribution in the corresponding F0u+(P03) – E0g+(P23) LIASE spectrum at approximately 5 μm is consistent with the vibrational populations in the E0g+(P23) state determined by the analysis of the UV fluorescence.
- Amplified spontaneous emission
- Ion-pair state
- Molecular chlorine