A completely solid state Ti:sapphire laser system for lidar and atmospheric spectroscopy

Abstract

Since many NASA lidar missions have restrictions on the weight, power and size of the instruments employed, we have designed and constructed a compact, completely solid state, passively cooled, tunable laser system. This Ti:sapphire-based laser system is pumped with a frequency-doubled, diode-pumped Nd:YAG laser and exhibits a tuning range 750-800 nm. The resulting Ti:sapphire radiation has a peak pulse energy of 0.218 mJ in a 16.8 ns gain-switched pulse, when pumped with 0.95 mJ of doubled Nd:YAG radiation of the same pulsewidth. Potassium titanyl phosphate, a nonlinear type II doubler, is used to shift the Nd:YAG radiation from 1064 to 532 nm with 50% doubling efficiency. Overall, the system exhibits an optical-to-optical efficiency of 0.5% from the pump diodes to the Ti:sapphire output. We have also demonstrated close agreement between our experimental results and theoretical modelling of the system. This firm understanding gives us the ability to scale the system to meet laser requirements for specific missions.