An investigation on structural, optical and enhanced third order nonlinear optical properties of facilely synthesized Ce:CuS nanosheets

Abstract

Current work reported facile chemical synthesis of hexagonal covellite CuS nanostructures with 0.0, 1.0, 3.0 and 5.0 wt% cerium doping concentrations. Scherrer’s equation used to determine the crystallites size and preferred orientation of growth plane is found along (110). Raman spectra of CuS nanostructures showed the characteristics sharp peak at the ∼ 472.21 cm−1. SEM images revealed the shape of nanostructures as nanosheets (NSs) for Ce:CuS. The band gap values of Ce:CuS NSs was computed from diffuse reflectance spectra (DRS) using Kubelka-Munk (K-M) theory which was found in range of 1.56–1.85 eV. Red and UV emission band of nanostructures can be seen in Photoluminescence spectra clearly. Third order nonlinear optics were performed by Z-scan techniques via femtosecond fiber pulsed laser. The nonlinear absorption coefficients (β) and nonlinear refractive index (n2) were found in range of 1.14 × 10-8–2.04 × 10-8 cm/W and 1.04 × 10-12–1.38 × 10-12 cm2/W, respectively. The value of third order nonlinear optical susceptibility (χ(3)) was noticed ∼ 3.36 × 10-8–5.48 × 10-8 esu. A significant improvement was observed in χ(3) with Ce incorporation in CuS lattice system. Therefore, Ce doping makes CuS potential nonlinear optical material for modern photonics device applications.