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arXiv · 1402.6529

Femtosecond pulse generation from a Topological Insulator mode-locked fiber laser

Abstract

We reported on the generation of femtosecond pulse in an anomalous-dispersion fiber ring laser by using a polyvinyl alcohol (PVA)-based Topological Insulator (TI), Bi2Se3 saturable absorber (SA). The PVA-TI composite has a low saturable optical intensity of 12 MW/cm2 and a modulation depth of ~3.9%. By incorporating the fabricated PVA-TISA into a fiber laser, mode-locking operation could be achieved at a low pump threshold of 25 mW. After an optimization of the cavity parameters, optical pulse with ~660 fs centered at 1557.5 nm wavelength had been generated. The experimental results demonstrate that the PVA could be an excellent host material for fabricating high-performance TISA, and also indicate that the filmy PVA-TISA is indeed a good candidate for ultrafast saturable absorption device.

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Hao Liu, Xu-Wu Zheng, Meng Liu, Nian Zhao, Ai-Ping Luo, Zhi-Chao Luo, Wen-Cheng Xu, Han Zhang, Chu-Jun Zhao, Shuang-Chun Wen. 2014-02-26. Femtosecond pulse generation from a Topological Insulator mode-locked fiber laser. https://doi.org/10.1364/oe.22.006868

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