Self Q-switched Mode-locking in a diode-pumped Nd：YVO4 laser

• Main Authors: You-Sheng Zhong, 鐘祐笙
• Other Authors: Hsiao-Hua Wu
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/20905780920602569696

碩士 === 東海大學 === 物理學系 === 89 === We found self Q-switched mode locking can occur in a low power free running Nd：YVO4 laser without additional switch element inserted in a plane-plane cavity except for a lens and a gain medium which is end pumped by a diode laser. Spontaneous giant spike takes place when the cavity configuration is adjust near the border of stability region where the beam spot size is shrink on the plane mirrors and diverge on the lens. Stable pulses with pulse width of 100-400 ns and repetition rate of 150-600 KHz for Q-switching as well as pulse width of 250-400 ps and repetition rate of 250-500 MHz for mode-locking have been generated in the experiment under pump power range from 240 to 800 mW. The self Q-switched mode locking is associated with Kerr lens effect in Nd：YVO4 crystal to reduce diffractive loss introduced by finite aperture of the lens.