Injection-seeded pulsed Ti:sapphire laser with novel stabilization scheme and capability of dual-wavelength operation

A gain-switched, single-frequency titanium-sapphire laser for atmospheric humidity measurements using the differential absorption lidar technique operating in the 820 run wavelength region is described. The laser is pumped by a frequency-doubled, flashlamp-pumped Nd:YAG laser at a repetition rate of 50 Hz and injection seeded by two external-cavity-diode lasers. The system yields pulses with an energy of 15 mJ and high spectral purity. We describe a novel active injection-locking technique that avoids the problems of established methods like dither-lock or ramp-and-fire. Furthermore, our method opens the possibility to switch between two wavelengths for alternating shots, in contrast to most established techniques that only allow operation at one wavelength. (c) 2005 Optical Society of America.