Investigations on the Growth and Characterization of L-Leucine Doped Rubidium Sulfate Nonlinear Optical Single Crystal

Abstract

Objectives: To grow crystal of inorganic material Rubidium sulfate by doping with an organic material L-leucine. Methods: Crystal has been grown by solution method. Crystallographic studies were done. Mechanical studies were carried out to find the mechanical strength and other parameters. Dielectric studies of L-leucine doped rubidium sulfate crystals were carried out to evaluate dielectric constant, dielectric loss and activation energy. UV-visible-NIR spectral studies were done in the wavelength range 200-1100 nm. Second order Non Linear Optical (NLO) studies of the grown crystal of LLRS were carried out by Kurtz-Perry technique. Findings: The grown LLRS crystal is observed to be crystallizing in orthorhombic structure by single crystal XRD studies. The optical band gap of LLRS crystal was found to be slightly more than that of undoped rubidium sulphate crystal. The SHG efficiency of LLRS crystal is observed to be 0.61 times that of the reference KDP sample. Dielectric parameters are found to decrease with increase in frequency. Dielectric constant and dielectric loss factor increase when the temperature of the samples increases. AC conductivity increases with increase of temperature. Activation energy is increasing when the frequency increases. The band gap value is found to be 4.43 eV for undoped rubidium sulfate crystal. For L-leucine doped rubidium sulfate (LLRS) crystal, the optical band gap is 4.48 eV. From the Microhardness teat, it is observed that the hardness increases with increase of the applied load for both the samples and this is due to reverse indentation size effect. Novelty: In this study, as a novel work, a very first attempt has been made to combine an organic material L-leucine with an inorganic crystal viz. rubidium sulfate to alter its physical and chemical properties.