Mechanical, electrical, linear, and nonlinear optical behavior of gamma-irradiated thiourea-doped lithium sulfate single crystals

Abstract

A thiourea-doped lithium sulfate single crystal was grown by the solution growth slow evaporation technique. The unit cell parameters of the grown crystal determined by X-ray diffraction (XRD) studies indicated that the crystal belongs to a monoclinic crystal system with noncentrosymmetric space group P2. Ultraviolet–visible spectral study signified that the crystal possesses an energy gap of 4.54 eV with 68% transparency in the visible region. The grown crystals were irradiated by Co-60 gamma radiation with different doses of 10 kGy, 30 kGy, and 50 kGy and the effects on powder XRD, dielectric properties, mechanical hardness, linear transmittance, and second harmonic generation (SHG) of the crystal were studied. It is observed that the crystallite size, energy gap, and transparency decreased, whereas the dielectric constant, AC conductivity, microhardness, and SHG efficiency increased with an increase in radiation dose.