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arXiv · 2012.08856

High-efficiency water-window x-ray generation from nanowire array targets irradiated with femtosecond laser pulses

Yinren Shou·Defeng Kong·Pengjie Wang·Zhusong Mei·Zhengxuan Cao·Zhuo Pan·Yunhui Li·Shirui Xu·Guijun Qi·Shiyou Chen·Jiarui Zhao·Yanying Zhao·Changbo Fu·Wen Luo·Guoqiang Zhang·Xueqing Yan·Wenjun Ma
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Abstract

We demonstrate the high-efficiency generation of water-window soft x-ray emissions from polyethylene nanowire array targets irradiated by femtosecond laser pulses at the intensity of 4*10^19 W/cm^2. The experimental results indicate more than one order of magnitude enhancement of the water-window x-ray emissions from the nanowire array targets compared to the planar targets. The highest energy conversion efficiency from laser to water-window x-rays is measured as 0.5%/sr, which comes from the targets with the longest nanowires. Supported by particle-in-cell simulations and atomic kinetic codes, the physics that leads to the high conversion efficiency is discussed.

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Yinren Shou, Defeng Kong, Pengjie Wang, Zhusong Mei, Zhengxuan Cao, Zhuo Pan, Yunhui Li, Shirui Xu, Guijun Qi, Shiyou Chen, Jiarui Zhao, Yanying Zhao, Changbo Fu, Wen Luo, Guoqiang Zhang, Xueqing Yan, Wenjun Ma. 2020-12-16. High-efficiency water-window x-ray generation from nanowire array targets irradiated with femtosecond laser pulses. https://doi.org/10.1364/oe.417512

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