The enhanced nonlinear absorption, nonlinear refraction and optical limiting properties of Bi2WO6/ZnO composites

The Bi 2 WO 6 /ZnO (BWO/ZnO) composites were synthesized by using a hydrothermal method. Then, the BWO/ZnO composites were poured into methyl methacrylate through polymerization to make the BWO/ZnO/PMMA organic glasses (OGs) with different amounts. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to investigate the crystal structures and morphology size of BWO/ZnO composites. The nonlinear absorption (NLA), nonlinear refraction (NLR) and optical limiting (OL) properties were systematically investigated by using the Z-scan technique at 532 nm. The BWO/PMMA and BWO/ZnO/PMMA OGs may transform from saturable absorption (SA) to reverse saturable absorption (RSA) by varying the input energy. The NLA, NLR and OL performances of the BWO/ZnO/PMMA OGs are superior to those of the BWO/PMMA OGs and other bismuth-based metal oxides. The synergistic interaction of BWO and ZnO plays a crucial role in the BWO/ZnO/PMMA OGs. The NLA mechanisms were analyzed using an energy-level model.