Chu Yuxi, Liang Xiaoyan, Yu Lianghong, Xu Yi, Xu Lu, Ma Lin, Lu Xiaoming, Liu Yanqi, Leng Yuxin, Li Ruxin, Xu Zhizhan
Opt Express. 2013 Dec 2;21(24):29231-9. doi: 10.1364/OE.21.029231.
We report on a 2.0 PW femtosecond laser system at 800 nm based on the scheme of chirped pulse amplification using Ti:sapphire crystals, which is the highest peak power ever achieved from a femtosecond laser system. Combining the index-matching cladding technique and the precise control of the time delay between the input seed pulse and pump pulses, the parasitic lasing in the final booster amplifier is effectively suppressed at the pump energy of 140 J at 527 nm. The maximum output energy from the final amplifier is 72.6 J, corresponding to a conversion efficiency of 47.2% from the pump energy to the output laser energy. The measured spectral width of the amplified output pulse from the final amplifier is 60.8 nm for the full width at half-maximum (FWHM) by controlling the spectral evolution in the amplifier chain, and the recompressed pulse duration is 26.0 fs. The technology of cross-polarized wave (XPW) is applied in a broadband front-end, and the pulse contrast is improved to ~1.5 × 10¹¹ (-100 ps before the main pulse) which is measured at 83 TW power level with a repetition rate of 5 HZ.
我们报道了一种基于啁啾脉冲放大方案、采用钛宝石晶体的800纳米2.0拍瓦飞秒激光系统，这是飞秒激光系统所达到的最高峰值功率。结合折射率匹配包层技术以及对输入种子脉冲和泵浦脉冲之间时间延迟的精确控制，在527纳米泵浦能量为140焦时，最终放大增强器中的寄生激光得到有效抑制。最终放大器的最大输出能量为72.6焦，对应从泵浦能量到输出激光能量的转换效率为47.2%。通过控制放大器链中的光谱演化，最终放大器放大输出脉冲的半高全宽（FWHM）测量光谱宽度为60.8纳米， recompressed脉冲持续时间为26.0飞秒。交叉偏振波（XPW）技术应用于宽带前端，脉冲对比度提高到约1.5×10¹¹（主脉冲前-100皮秒），这是在83太瓦功率水平、5赫兹重复频率下测量得到的。
