CHARACTERISTICS OF LASER-EMISSION AND GAIN ON COMPETING TRANSITIONS IN AN SR+ RECOMBINATION LASER

Laser action at 416.2 nm as well as 430.5 nm was investigated in a low -repetition-rate strontium-ion recombination laser incorporating a dis persive cavity. At best 35% of the pulse energy at 430.5 nm was availa ble at 416.2 nm and the temporal width of the 416.2 nm laser emission was 10 to 100 ns (FWHM) shorter than that at 430.5 nm. Peak axial smal l-signal gains were also measured for both transitions. The optimum sm all-signal gain at 430.5 nm was 8.3% cm(-1) while the small-signal gai n at 416.2 nm ranged from 1 to 2% cm(-1) over a variety of discharge c onditions. It is concluded that the ratios of gain and pulse energy at 430.5 nm to that at 416.2 nm imply partial electron collisional mixin g between the lower laser levels Sr II 5(2)P(3/2) and 5(2)P(1/2).