皮秒激光行波放大器研究

Research on Picosecond Laser Traveling Wave Amplifier

利用SESAM光纤锁模激光器作为种子源,设计了行波放大器,对皮秒脉冲的放大特性进行了研究。利用中心波长为885 nm的光纤耦合半导体激光器直接泵浦Nd:YVO_(4)晶体,有效降低了晶体中的热效应。通过两级行波放大,在泵浦功率为222 W时,获得了平均功率为33.7 W,重复频率为70.4 MHz,脉冲宽度为9.4 ps的脉冲输出。输出激光光束具有较好的圆度,光束质量因子M^(2)在x方向上为1.15,y方向上为1.13。在8 h的连续运转下,激光器功率抖动性RMS<1%。

In this paper,a traveling wave amplifier is designed using a SESAM fiber mode-locked laser as the seed source and the amplification performance of picosecond pulses is studied.The Nd:YVO_(4) crystal is pumped directly by a fiber-coupled semiconductor laser with a central wavelength of 885 nm,and the thermal effect in the crystal is effectively reduced.By two-stage traveling wave amplification,the output pulses with average power of 33.7 W,repetition frequency of 70.4 MHz and pulse width of 9.4 ps were obtained under the pump power of 222 W.The beam quality factor M^(2) is 1.15 in x direction and 1.13 in y direction.The output power jitter RMS of the laser is less than 1%under 8 hours continuous operation.