Structural, linear and nonlinear optical properties of Pb(Mg1/3Nb2/3)O3-PbTiO3 nanoparticles.

Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ nanoparticles were synthesized by solid-state route. The crystal structure and optical properties were characterized by X-ray diffraction and UV–visible spectroscopy. X-ray diffraction confirmed the perovskite structure and the mean size of the crystallites was determined by employing the Williamson–Hall (W–H) model. From the UV–Visible measurements, several fundamental optical properties such as transmittance, absorbance, refractive index, band gap (E_g), Urbach energy, optical conductivity, dielectric function, and absorption coefficient were determined. The band gap energy was found to be around 3.05 eV with a high transmittance value for high wavelength. Further, the optical data were utilized to investigate the linear susceptibility, third-order nonlinear optical susceptibility, and nonlinear refractive index of the sample. It is found that the values of χ(¹), χ(³) and n₂ were equal to 0.053 esu, 1.33 × 10⁻¹⁵ esu, and 3.88 × 10⁻¹⁴ esu, respectively. [ABSTRACT FROM AUTHOR]