论文部分内容阅读
为了获得高重复频率的飞秒激光脉冲,将突发运行模式引入飞秒碟片再生放大系统中。通过将再生放大器的腔长设计为9.3m,激光系统输出了接近衍射极限的激光脉冲,且激光脉冲的重复频率为电光调制频率的5倍。在电光调制频率为5kHz、吸收的抽运功率为98 W的条件下,获得了最高输出功率为10.7 W、光谱半峰全宽为1.18nm、脉冲宽度为777fs的双曲正割脉冲输出。再生放大器的光-光转换效率随着电光调制频率的增加而增加,从频率为0.5kHz时的12.4%增加到频率为5kHz时的25.3%。激光的输出稳定性在18~20℃的温度区间内随着水冷温度的降低而提高,激光系统输出功率的均方根从20℃时的0.93%变为18℃时的0.52%。该研究结果对于设计具有高重复频率、高功率且性能稳定的飞秒激光系统具有参考价值。
In order to obtain high repetition rate femtosecond laser pulses, the burst mode is introduced into the femtosecond disk regeneration and amplification system. By designing the length of the regenerative amplifier as 9.3 m, the laser system outputs a laser pulse near the diffraction limit, and the repetition frequency of the laser pulse is five times that of the electro-optic modulation frequency. The hyperbolic secant pulse output with the highest output power of 10.7 W, the full width at half maximum of 1.18 nm and the pulse width of 777 fs was obtained under the condition of the electro-optic modulation frequency of 5 kHz and the absorbed pumping power of 98 W. The optical-to-optical conversion efficiency of a regenerative amplifier increases with the electro-optic modulation frequency, from 12.4% at a frequency of 0.5 kHz to 25.3% at a frequency of 5 kHz. The laser output stability increases with decreasing water cooling temperature in the temperature range of 18 ~ 20 ℃. The root mean square of laser system output power changes from 0.93% at 20 ℃ to 0.52% at 18 ℃. The results of this study are valuable for designing femtosecond laser systems with high repetition rate, high power and stable performance.