Structural and nonlinear optical absorption studies of Mn doped PbWO4 nanoparticles

Abstract

Manganese (Mn) -doped PbWO4 nanostructures with different concentration of Mn have been synthesized by chemical precipitation method followed by thermal annealing. The influence of Mn on the structural, optical and morphological properties was systematically investigated by various spectral-analytical techniques. X-ray diffraction (XRD) study reveals the successful incorporation of Mn into PbWO4 lattice without any secondary phase formation. From the UV–Vis spectra, it is clear that the dopant has shifted the absorption towards higher wavelength. Photoluminescence measurements showed a broad blue-green emission band with a maximum emission peak centered at 490 nm. The magnetic investigation further evidences the transport of dia to paramagnetism of Mn-doped PbWO4 and weak contribution of ferromagnetism at low magnetic field. It can be due to the effect of Mn clusters in host lattice and led to the changes in the magnetic properties. Typical third order nonlinearity of the proposed Mn-doped PbWO4 nanostructures has been investigated by an open aperture Z-scan technique using 10 ns Nd:YAG laser pulses operating at 532 nm. The nonlinear absorption data suggests that two photon absorption as the dominant nonlinear mechanism. A good nonlinear optical absorption is observed for both pure and doped nanostructures and the nonlinearity increases linearly with increase in Mn concentration.