论文部分内容阅读
通过在钛宝石激光腔内引入望远镜长腔系统增加腔长,实现了重复频率低到10MHz的飞秒激光振荡,在5W的抽运功率下获得了平均输出功率200mW、单脉冲能量20nJ的稳定输出.在此基础上分析了腔内不同色散情况下的输出脉冲光谱和脉宽特性,结果表明在腔内存在一定负色散的情况下,锁模脉宽可接近转换极限,最短脉宽可达56fs.而在正色散的情况下,锁模输出的脉宽较宽,并且随着腔内正色散的增多,脉宽可到大于600fs,锁模光谱也呈马鞍形.
By introducing a telescope long cavity system in the sapphire laser cavity to increase the cavity length, a femtosecond laser oscillation with a repetition frequency as low as 10 MHz is realized, an average output power of 200 mW at a pumping power of 5W and a stable output with a single pulse energy of 20 nJ Based on the analysis of the output pulse spectrum and pulse width characteristics under different dispersion conditions in the cavity, the results show that the mode-locked pulse width can approach the conversion limit with a certain negative dispersion in the cavity, the shortest pulse width can reach 56fs In the case of positive dispersion, the pulse width of the mode-locked output is wide, and with the increase of positive dispersion in the cavity, the pulse width can be larger than 600fs and the mode-locked spectrum is also saddle-shaped.