Q-switched mode locking of Nd:YAG lasers by hybrid active and passive mechanisms

• Main Authors: Su, Huan-Rui, 蘇桓銳
• Other Authors: Wu, Hsiao-Hua
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/33598935719840420612

碩士 === 東海大學 === 物理學系 === 99 === This thesis studies Q-switched mode locking of Nd:YAG lasers by using active mode-locked technique in combination of gain switched or passive Q-switched technique. In the gain-switched experiment, Q-switched mode-locked pulses were observed when the modulation frequency tuned to resonate with natural frequency of the laser system. A four to five times enhancement of peak power and an improvement of mode-locked performance can be obtained by applying active mode locking to the gain-switched experiment. In passive Q-switched experiment, we have also observed Q-switched mode-locked pulses. The conditions for generating Q-switched pulses by optimizing average output power, repetition rate, and peak power were studied. In these cases, Q-switched pulses with average output power as high as 12 mW, repetition rate up to 20 KHz, and pulse width as low as 200 ns were obtained. By applying active mode locking to passive Q-switched experiment, the mode-locked performance improvement together with a three times increment of peak power could also be achieved.