Multiple-fringe structure of attosecond transient absorption spectrum driven by mid-infrared laser
We theoretically investigate delay-dependent attosecond transient absorption spectra in the helium atom dressed by an infrared laser pulse in the wavelength range of 800–2400 nm. By numerically solving the three-dimensional time-dependent Schrödinger equation, we find that the absorption spectrogram exhibits a multiple-fringe structure for using the longer-wavelength dressing pulse. The quantitative calculation of the transition matrix between different Floquet states provides direct evidence on the origin of the multiple-fringe structure. Our result shows that the wavelength of the dressing pulse is an important parameter and the unique feature of attosecond transient absorption spectroscopy can be induced in the mid-infrared regime.
Xue Jinxing,Liu Candong,Zeng Zhinan,Li Ruxin,Xu ZhiZhan. Multiple-fringe structure of attosecond transient absorption spectrum driven by mid-infrared laser[J].Chinese Optics Letters,2019,17(8):08.