Abstract

We report the first direct evidence that there is collisional mixing between the ²P_3/2 and ²P_1/2 levels of the copper-vapor laser (CVL), which is excited by a resonant tunable UV laser. When the ²P_1/2 level is pumped which generates a yellow laser line (578.2 nm) by a transition to the ²D_3/2 level, the ²P_3/2 level is also populated, producing a strong green laser line (510.6 nm). On the other hand, when the ²P_3/2 level is excited which produces a green laser line by a transition to the ²D_5/2 level, the ²P_1/2—²D_3/2 transition is only weakly stimulated. The collisional mixing takes place in a wide range of He buffer gas pressure: 20-600 Torr. Below 20 Torr, only the primarily pumped level is strongly stimulated. The asymmetric mixing has significant implications for high-pressure transverse discharge CVLs.¹ Also, we observed that each transition is stimulated even when the pump laser is detuned as far as 1 nm from the resonance wavelength, indicating that they are collision-induced stimulated emission.

© 1987 Optical Society of America