Investigation of optical property in LiInSe2 single crystal grown by Bridgman Stockbarger method using stepper translations for mid IR laser application

Abstract

Abstract LiInSe 2 polycrystalline material was synthesized in a horizontal muffle furnace with the help of a mechanical motor. LiInSe 2 single crystal has successfully been grown by modified Bridgman furnace using stepper translation. The grown crystal was subjected to various characterizations such as Powder X-ray Diffraction (XRD), Single crystal X-ray Diffraction, High Resolution X-ray Diffraction (HRXRD), Fourier transform infrared spectroscopy (FTIR), Ultraviolet–Visible-Near Infrared spectroscopy (UV–Vis–NIR), Photoluminescence and Micro Raman spectroscopy. The grown LiInSe 2 crystal was confirmed by single crystal and powder X-ray diffraction analyses. The FTIR transmission of grown LiInSe 2 single crystal was found to be around 80% which is being used in the field of mid Infrared laser, Lidar sensor, and optical parametric conversion. The band gap energy 1.85 eV was calculated from absorption spectrum. The cut off wave length is 617 nm for LiInSe 2. The photoluminescence spectrum was observed around 598 nm at ambient temperature, corresponding energy is 2.07 eV. The structural and compositional uniformities of LiInSe 2 were studied using micro-Raman scattering spectroscopy at room temperature. The insignificant change in the Full width at half maximum (FWHM) of the Г 1 ( W 1 ) measured at different regions of the crystal further reveals that the composition throughout its length is fairly uniform.