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arXiv · 1712.09182

Relativistic, single-cycle tunable-infrared pulses generated by a tailored plasma density structure

Zan Nie·Chih-Hao Pai·Jianfei Hua·Chaojie Zhang·Yipeng Wu·Yang Wan·Fei Li·Jie Zhang·Zhi Cheng·Qianqian Su·Shuang Liu·Yue Ma·Xiaonan Ning·Yunxiao He·Wei Lu·Hsu-Hsin Chu·Jyhpyng Wang·Warren B. Mori·Chan Joshi
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Abstract

The availability of intense, ultrashort coherent radiation sources in the infrared region of the spectrum is enabling the generation of attosecond X-ray pulses via high harmonic generation, pump-probe experiments in the "molecular fingerprint" region and opening up the area of relativistic-infrared nonlinear optics of plasmas. These applications would benefit from multi-millijoule single-cycle pulses in the mid to long wavelength infrared (LW-IR) region. Here we present a new scheme capable of producing tunable relativistically intense, single-cycle infrared pulses from 5-14$\mu$m with a 1.7% conversion efficiency based on a photon frequency downshifting scheme that uses a tailored plasma density structure. The carrier-envelope phase (CEP) of the LW-IR pulse is locked to that of the drive laser to within a few percent. Such a versatile tunable IR source may meet the demands of many cutting-edge applications in strong-field physics and greatly promote their development.

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Zan Nie, Chih-Hao Pai, Jianfei Hua, Chaojie Zhang, Yipeng Wu, Yang Wan, Fei Li, Jie Zhang, Zhi Cheng, Qianqian Su, Shuang Liu, Yue Ma, Xiaonan Ning, Yunxiao He, Wei Lu, Hsu-Hsin Chu, Jyhpyng Wang, Warren B. Mori, Chan Joshi. 2017-12-26. Relativistic, single-cycle tunable-infrared pulses generated by a tailored plasma density structure. https://doi.org/10.1038/s41566-018-0190-8

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