Facile synthesis of two-dimensional WS2 with reverse saturable absorption and nonlinear refraction properties in the PMMA matrix.

We report a versatile, cost-effective and reproducible solid-state reaction approach to synthesize two-dimensional (2D) WS 2 with strong nonlinear optical performances. The reverse saturable absorption and nonlinear refraction properties of 2D WS 2 incorporated into PMMA were measured by the z-scan configuration under femtosecond pulses at 800 nm. The figure of merit and the nonlinear optical refractive index n 2 were calculated to be ∼ 0.40 × 10 −13 esu cm and ∼ 3.34 × 10 −4 cm 2 /GW, respectively. Furthermore, optical limiting (OL) effects of the WS 2 /PMMA composite were observed with OL threshold F OL ∼ 2.4 mJ/cm 2 , which is lower than those of previously reported OL materials. Such results imply the WS 2 /PMMA composite as a potential candidate for practical OL applications and the solid-state reaction technology provides a feasible approach for the preparation of 2D WS 2 applied in the field of nanophotonics. [ABSTRACT FROM AUTHOR]