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arXiv · 2110.09082

Wavelength-tunable doughnut beam generation using few-mode long-period fiber grating

Kuei-Huei Lin·Wen-Hsuan Kuan
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Abstract

Ultra-broadband long-period fiber grating with 10-dB bandwidth of 155 nm and 3-dB bandwidth of 415 nm is demonstrated around 1060 nm, which has been combined with a tunable ytterbium-doped fiber laser to generate optical doughnut beams in the spectral range from 1030 nm to 1099 nm, and the vector nature of generated optical fields are observed. The long-period fiber grating has also been used to transform the amplified spontaneous emission of an ytterbium-doped fiber amplifier into a broadband optical doughnut beam.

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Kuei-Huei Lin, Wen-Hsuan Kuan. 2021-10-18. Wavelength-tunable doughnut beam generation using few-mode long-period fiber grating. https://arxiv.org/abs/2110.09082

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