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arXiv · 1508.01631

Surfactant-aided exfoliation of molydenum disulphide for ultrafast pulse generation through edge-state saturable absorption

Richard C. T. Howe·Robert I. Woodward·Guohua Hu·Zongyin Yang·Edmund J. R. Kelleher·Tawfique Hasan
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Abstract

We use liquid phase exfoliation to produce dispersions of molybdenum disulphide (MoS2) nanoflakes in aqueous surfactant solutions. The chemical structures of the bile salt surfactants play a crucial role in the exfoliation and stabilization of MoS2. The resultant MoS2 dispersions are heavily enriched in single and few (<6) layer flakes with large edge to surface area ratio. We use the dispersions to fabricate free-standing polymer composite wide-band saturable absorbers to develop mode-locked and Q- switched fibre lasers, tunable from 1535-1565 and 1030-1070 nm, respectively. We attribute this sub-bandgap optical absorption and its nonlinear saturation behaviour to edge-mediated states introduced within the material band-gap of the exfoliated MoS2 nanoflakes.

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Richard C. T. Howe, Robert I. Woodward, Guohua Hu, Zongyin Yang, Edmund J. R. Kelleher, Tawfique Hasan. 2015-08-07. Surfactant-aided exfoliation of molydenum disulphide for ultrafast pulse generation through edge-state saturable absorption. https://arxiv.org/abs/1508.01631

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