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arXiv · 2001.01386

Passively mode-locked thulium-doped all-fiber laser based on low V number fiber bending

Hongbo Jiang·Yunpeng Huang·Zihao Zhao·Lei Jin·Shinji Yamashita·Sze Y. Set
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Abstract

This paper describes a mode locking technique based on enhanced polarization dependent loss (PDL). The method utilizes a bent single mode fiber (SMF28) coil to induce sufficient PDL at 2 \(μ\)m wavelength region. Significant PDL in SMF28 coils is enabled since the light is much more weakly guided. A passively mode-locked thulium doped all-fiber laser is demonstrated using this simple device with polarization controllers as mode locker. The results indicate a moderate amount of 1 dB is sufficient to initiate and sustain stable mode-locking operation. We believe, to the best of our knowledge, this is the first demonstration of mode-locked fiber laser fully based on polarization dependent property of bent fiber section.

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Hongbo Jiang, Yunpeng Huang, Zihao Zhao, Lei Jin, Shinji Yamashita, Sze Y. Set. 2020-01-06. Passively mode-locked thulium-doped all-fiber laser based on low V number fiber bending. https://arxiv.org/abs/2001.01386

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