Energetic few-cycle pulse compression in gas-filled hollow core fiber with concentric phase mask
Zhao Yu1, 2, Huang Zhi-Yuan1, 2, Zhao Rui-Rui1, 2, Wang Ding1, †, Leng Yu-Xin1, ‡
       

(a)–(d) Output power spectra of input pulses passing through concentric phase mask with input energy values ranging from 5.0 mJ to 20.0 mJ.