Saturable absorption and self-focusing properties of copper molybdate with flower structure

Abstract

Copper molybdate (CuMoO4) nanomaterial was synthesized by an ultrasonic method. The successful synthesis of CuMoO4 was testified by Raman spectrum. The scanning electron microscopy (SEM) analysis reveals that the CuMoO4 exhibits irregular flower structure. The average thickness of each petal is about 30 nm. The CuMoO4 was dispersed into methyl methacrylate (MMA) to fabricate CuMoO4/PMMA organic glass with different amounts. The band gap (Eg) of CuMoO4/PMMA is about 2.28 eV obtained from the conversion of the ultraviolet-visible (UV-Vis) absorption spectra. The nonlinear absorption (NLA) and nonlinear refraction (NLR) of CuMoO4/PMMA organic glass were measured by the Z-scan technique. The CuMoO4/PMMA organic glass exhibits saturable absorption (SA) and self-focusing effect. The saturable light intensity, NLA coefficient and NLR coefficient are Is = 6.8 MW cm−2, β = –109 cm GW−1 and γ = 2.43 × 10−6 cm2 MW−1 at the incident energy of 20 μJ, respectively. At the same incident energy of 20 μJ, the Is value of CuMoO4/PMMA is about half that of NiMoO4/PMMA. Therefore, the CuMoO4 nanomaterial is easier to exhibit saturable absorption (SA). It is found that T < 1, W> 1 by analyzing the figures of merit for CuMoO4/PMMA. Therefore, the NLR of CuMoO4/PMMA is dominate. The results show that CuMoO4 nanomaterial has potential applications in lasers and optical switches.