Narrow-linewidth, tunable ultraviolet, Ti:sapphire laser for environmental sensing

We describe a compact, narrow-linewidth, etalon-tuned titanium:sapphire laser cavity that is designed for field environmental sensing and is pumped by the second harmonic of a kilohertz Nd:YAG laser. The fundamental tunable range is from 690 to 1100 nm, depending on mirror reflectivities and the optics kit used. The conversion efficiency is at least 25% for the fundamental and 2-3% for intracavity frequency doubling from 3.5 to 4 W 532 nm pump power. The linewidth is <0.1 cm^-1, and the pulse width is 18 ns. Applications of this cavity include the measurement of trace gas species by laser-induced fluorescence, cavity ringdown spectroscopy, and micropulse lidar in the UV-visible regions.