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arXiv · 1504.05130

Spatiotemporal focusing does not always improve axial intensity localization

Ya Cheng·Hongqiang Xie·Zhaohui Wang·Guihua Li·Bin Zeng·Fei He·Wei Chu·Jinping Yao·Lingling Qiao
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Abstract

We report on an experimental comparison on critical intensities of nonlinear self-focusing in air with conventional focusing and spatiotemporal focusing schemes. Our results show that the conventional focusing with the focal lens completely filled with the incident beam allows for the strongest axial intensity confinement against the self-focusing effect. This is because that in the high-numerical-aperture condition, the focal spot will have a compact size which results in a high focal intensity. Meanwhile, the Rayleigh length of the focused beam will be substantially shortened which efficiently postpones the onset of self-focusing.

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Ya Cheng, Hongqiang Xie, Zhaohui Wang, Guihua Li, Bin Zeng, Fei He, Wei Chu, Jinping Yao, Lingling Qiao. 2015-04-20. Spatiotemporal focusing does not always improve axial intensity localization. https://arxiv.org/abs/1504.05130

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