Orange, yellow and green emissions generated in Q-switched Nd:YALO3/YVO4 Raman laser

Nd:YAlO3/YVO4 crystal Raman laser with orange, yellow and green emission switchable output was demonstrated by the second-harmonic generation and sum-frequency generation of the fundamental and the first-Stokes waves. A diode-end-pumped acousto-optic Q-switched Nd:YAlO3 crystal laser at 1080 nm was used to drive a 30 mm length YVO4 crystal for intra-cavity Raman operation. The different visible sources were achieved in an angle-tuned BBO crystal. The average output power of 539.9 nm green light, 567.2 nm yellow light and 597.4 nm orange light generated in a BBO crystal with single direction were 418, 266 and 361 mW at an absorbed pump power of 6.01 W and a pulse repetition frequency of 20 kHz, with respective to pulse widths of about 47.2, 4.8 and 5.6 ns. The results show that the angle-tuned BBO crystal with characteristics of large temperature tolerance and large nonlinear optical coefficient was a promising nonlinear optical crystal for wavelength-switching in the Q-switched Raman laser.