Influence of cutting off position of plasma filament formed by two-color femtosecond laser on terahertz generation
Xue Zhan-Qiang1, Shang Li-Ping1, 2, †, Deng Hu1, Zhang Qian-Cheng1, Liu Quan-Cheng1, Qu Wei-Wei1, Li Zhan-Feng3, Wang Shun-Li1
       

(color online) Two repetitions of THz amplitude and peak frequency at each cutting off position: (a) and (c) experimental results with the lens of f = 400 mm, (b) and (d) experiment results with the lens of f = 1000 mm.