Pulsed, tunable 900-1100 nm lasers: LiF:F/sub 2//sup +/ versus Ti/sup 3+/:sapphire

Summary form only given. Broadly tunable solid state lasers are required for applications such as LIDAR where multi-wavelength measurements can determine size, shape and distribution of atmospheric aerosols. However, in the important 900-1100 nm range, established reliable and efficient tunable solid state lasers are not currently available Although Ti:sapphire lasers do operate in this range, the gain of Ti/sup 3+/ is comparatively low at these wavelengths. To fill this spectral gap for LIDAR applications, we have developed and evaluated LiF:F/sub 2//sup +/ room temperature color center lasers pumped by 532 nm radiation. Since 532 nm matches the absorption bands of both F/sub 2/ and F/sub 2/*, the pump light is used to simultaneously create the laser active F/sub 2//sup +/ (by the two-step F/sub 2//spl rarr/F/sub 2/*/spl rarr/F/sub 2//sup */ process) and excite the F/sub 2//sup +/ centers. Here we show that LiF:F/sub 2//sup +/ operates with substantially lower thresholds, broader tuning, higher output pulse energies and shorter pulses than Ti:sapphire in the 90-1100 nm spectral region. The principal limitations on LiF:F/sub 2//sup +/ lasers are identified as ASE and a slow thermal degradation.