Passively Q-switched Nd:Sc0.2Y0.8SiO5 dual-wavelength laser with the orthogonally polarized output

We have demonstrated a laser-diode pumped continuous-wave (CW) and passively Q-switched laser with a Nd:Sc0.2Y0.8SiO5 (Nd:SYSO) crystal for the first time. In the CW operation, the laser was found to oscillate in tri-wavelength regime at 1074.8 nm, 1076.6 nm and 1078.2 nm, respectively. The maximum CW output power of 1.96 W was obtained, giving an optical-to-optical conversion efficiency of 35% and a slope efficiency of 39%. Using either Cr4+:YAG or V3+:YAG crystal as saturable absorber, stable passively Q-switched laser was obtained at dual-wavelength of 1074.8 nm and 1078.2 nm with orthogonal-polarization. The maximum average output power, pulse repetition rate, and shortest pulse width were 1.03 W, 50 kHz, and 24 ns, respectively. The passively Q-switched dual-wavelength laser could be potentially used as a source for generation of terahertz radiation. (C) 2012 Optical Society of America