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arXiv · 2108.01606

Optical vortex coronagraph imaging of a laser-induced plasma filament

Qingqing Liang·Xia Huang·Yanfei Mou·Shaodong Zhou·Wenxing Zhang·Jieyu Gui·Grover A. Swartzlander·JR.·Qingqing Cheng·Yi Liu
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Abstract

A high contrast imaging technique based on an optical vortex coronagraph (OVC) is used to measure the spatial phase profile induced by an air plasma generated by a femtosecond laser pulse. The sensitivity of the OVC method significantly surpassed both in-line holographic and direct imaging methods based on air plasma fluorescence. The estimated phase sensitivity of 0.046 waves provides opportunities for OVC applications in areas such as bioimaging, material characterization, as well as plasma diagnostics.

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Qingqing Liang, Xia Huang, Yanfei Mou, Shaodong Zhou, Wenxing Zhang, Jieyu Gui, Grover A. Swartzlander, JR., Qingqing Cheng, Yi Liu. 2021-08-03. Optical vortex coronagraph imaging of a laser-induced plasma filament. https://arxiv.org/abs/2108.01606

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