Use of GaAs as a passive Q-switch as well as an output coupler for diode-pumped Nd:YVO4 lasers

• Main Authors: Lin, Yao-chun, 林耀群
• Other Authors: 蒲念文
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/93917818462083697801

碩士 === 國防大學中正理工學院 === 應用物理研究所 === 94 === In this paper, we investigate an all-solid-state passive Q-switched Nd:YVO4 laser system. Q-switching operation is very common and important for diode-pumped solid-state lasers. And in recent years, Q-switched lasers have been used in many fields, such as nonlinear optics, range finding, medicine, and micromachining, etc. In this experiment, we use GaAs wafer as an important element for passive Q-switching. The GaAs wafer, which works as an saturable absorber, was used as the Q-switch in the laser system. Moreover, GaAs wafer also acts as an anti-resonant Fabry-Perot resonantor, so we use it as an output coupler. Its reflectance is 73.5%, and its transmittance is 26.5%. We use two gain media with different lengths. One is 6 mm, and the other is 3 mm. The results of this experiment are as follows: The cavity length is adjustable from 8 mm to 17 mm；the shotest pulse width is 7 ns；its photon lifetime is about 0.33 ns；the highest peak power is 314 W；the highest repetition rate is about 1.7 MHz；its pulse energy is up to 2.2 μJ.