Increase in Photon Flux of Attosecond Pulses
摘要
High-intensity attosecond pulses capable of inducing a two-photon process are desired to realize an attosecond pump–attosecond probe experiment. In this work, we show the increase of the intensity of attosecond pulses in the water-window region by combining a loose focusing method with high-energy mid-IR drivers. Meanwhile, the effectiveness of an ideal driving field waveform produced by a multi-wavelength synthesizer is demonstrated to improve the conversion efficiency.