Generation of subcycle isolated attosecond pulses by pumping ionizing gating

Zhaohui Wu; Hao Peng; Xiaoming Zeng; Zhaoli Li; 1 Zhimeng Zhang; 1 Huabao Cao; Yuxi Fu; Xiaodong Wang; Xiao Wang; Jie Mu; 1 Yanlei Zuo; C. Riconda; S. Weber; Jingqin Su

arXiv · 2212.06599

Generation of subcycle isolated attosecond pulses by pumping ionizing gating

Zhaohui Wu·Hao Peng·Xiaoming Zeng·Zhaoli Li·1 Zhimeng Zhang·1 Huabao Cao·Yuxi Fu·Xiaodong Wang·Xiao Wang·Jie Mu·1 Yanlei Zuo·C. Riconda·S. Weber·Jingqin Su

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Abstract

We present a novel approach named as pumping ionizing gating (PIG) for the generation of isolated attosecond pulses (IAPs). In this regime, a short laser is used to ionize a pre-existing gas grating, creating a fast-extending plasma grating(FEPG) having an ionization front propagating with the velocity of light. A low-intensity long counterpropagating pump pulse is then reflected by a very narrow region of the ionization front, only where the Bragg conditions for resonant reflection is satisfied. Consequently, the pump reflection is confined within a sub-cycle region called PIG, and forms a wide-band coherent IAP in combination with the frequency up-conversion effect due to the plasma gradient. This approach results in a new scheme to generate IAPs fromlong picosecond pump pulses. Three-dimensional (3D) simulations show that a 1.6-ps, 1-{\mu}m pump pulse can be used to generate a 330 as laser pulse with a peak intensity approximately 33 times that of the pump and a conversion efficiency of around 0.1%.These results highlight the potential of the PIG method for generating IAPs with high conversion efficiency and peak intensity.

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Zhaohui Wu, Hao Peng, Xiaoming Zeng, Zhaoli Li, 1 Zhimeng Zhang, 1 Huabao Cao, Yuxi Fu, Xiaodong Wang, Xiao Wang, Jie Mu, 1 Yanlei Zuo, C. Riconda, S. Weber, Jingqin Su. 2022-12-13. Generation of subcycle isolated attosecond pulses by pumping ionizing gating. https://arxiv.org/abs/2212.06599

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