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arXiv · 1311.1586

Second harmonic generation in a centrosymmetric gas medium with spatiotemporally focused intense femtosecond laser pulses

Guihua Li·Jielei Ni·Hongqiang Xie·Bin Zeng·Jinping Yao·Wei Chu·Haisu Zhang·Chenrui Jing·Fei He·Huailiang Xu·Ya Cheng·Zhizhan Xu
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Abstract

We demonstrate unexpectedly strong second harmonic generation (SHG) in Argon gas by use of spatiotemporally focused (SF) femtosecond laser pulses. The resulting SHG by the SF scheme at a 75 cm distance shows a significantly enhanced efficiency than that achieved with conventional focusing scheme, which offers a new promising possibility for standoff applications. Our theoretical calculations reasonably reproduce the experimental observations, which indicate that the observed SHG mainly originates from the gradient of nonuniform plasma dynamically controlled by the SF laser field.

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Guihua Li, Jielei Ni, Hongqiang Xie, Bin Zeng, Jinping Yao, Wei Chu, Haisu Zhang, Chenrui Jing, Fei He, Huailiang Xu, Ya Cheng, Zhizhan Xu. 2013-11-07. Second harmonic generation in a centrosymmetric gas medium with spatiotemporally focused intense femtosecond laser pulses. https://doi.org/10.1364/ol.39.000961

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