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arXiv · 1507.03188

Yb- and Er-doped fiber laser Q-switched with an optically uniform, broadband WS2 saturable absorber

M. Zhang·G. Hu·R. C. T. Howe·L. Chen·Z. Zheng·T. Hasan
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Abstract

We demonstrate a ytterbium (Yb) and an erbium (Er)-doped fiber laser Q-switched by a solution processed, optically uniform, few-layer tungsten disulfide saturable absorber (WS2-SA). Nonlinear optical absorption of the WS2-SA in the sub-bandgap region, attributed to the edge-induced states, is characterized by 3.1% and 4.9% modulation depths with 1.38 and 3.83 MW/cm2 saturation intensities at 1030 and 1558 nm, respectively. By integrating the optically uniform WS2-SA in the Yb- and Er-doped laser cavities, we obtain self-starting Q-switched pulses with microsecond duration and kilohertz repetition rates at 1030 and 1558 nm. Our work demonstrates broadband sub-bandgap saturable absorption of a single, solution processed WS2-SA, providing new potential efficacy for WS2 in ultrafast photonic applications.

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M. Zhang, G. Hu, R. C. T. Howe, L. Chen, Z. Zheng, T. Hasan. 2015-07-12. Yb- and Er-doped fiber laser Q-switched with an optically uniform, broadband WS2 saturable absorber. https://arxiv.org/abs/1507.03188

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