Chinese Optics Letters, Vol. 17, Issue 8, 082601 (2019)
Multiple-fringe structure of attosecond transient absorption spectrum driven by mid-infrared laser
Jinxing Xue1,2,3, Candong Liu1,2,*, Zhinan Zeng1,2,**, Ruxin Li1,2, and Zhizhan Xu1
- 1Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
- 2Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- 3University of Chinese Academy of Sciences, Beijing 100049, China
We theoretically investigate the 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 Schr dinger equation, we find that the absorption spectrogram exhibits a multiple-fringe structure for using the mid-infrared 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.