Thermal and Dielectric Properties Of L-Malic Acid Doped KDP Single Crystals

Abstract

Potassium Dihydrogen Phosphate (KDP) is a popular nonlinear optical materials that is widely used in the field of nonlinear optics for the frequency conversion processes. Optically good quality L-Malic acid doped KDP (LMKDP) crystals have been grown by slow evaporation method at room temperature. The crystallinity of the LMKDP crystals has been studied by powder XRD analysis. The presence of the functional group for LMKDP crystals are qualitatively analyzed from FTIR and FT-RAMAN spectrum. The second harmonic generation (SHG) efficiency was measured by using Kurtz powder technique. The dielectric behavior of grown crystals has been studied in the frequency range from 50 Hz to 50MHz. UV–visible absorption spectrum was recorded to study the optical transparency of grown crystal. Thermogravimetric analysis (TG) and differential thermal analysis (DTA) were used to study the thermal properties of the grown crystal. Introduction. In this modern era of information and technology with fast and high data storage capacity, data retrieving, processing and transmission demands the search of new NLO materials with unique physical properties. Hence, there is a great demand for synthesize the new NLO materials and grow their single crystals. KDP is among the most widely used NLO material. Potassium dihydrogen phosphate (KDP) crystals have created considerable interest because of its Piezo-electric, electro-optic, nonlinear optical properties and its extensive application in X-ray monochromators [1]. In addition to their large NLO response, the advantage of organic materials is that they offer high degree of synthetic flexibility to tailor their optical properties through the structural modification and they exhibit high laser damage threshold [2]. In single crystals form, the NLO materials display huge optical nonlinearity, which is of great interest for telecommunication, optical information processing and high optical data storage, etc., [3]. Many methods have been tried to improve the NLO properties of KDP crystal. With the aim of improving the second harmonic generation (SHG) efficiency of KDP, researchers have attempted to modify KDP crystals by doping different types of impurities. The present work, L-Malic acid of 0.2 molar percentages has been doped with KDP material. The grown L-Malic acid doped KDP (LMKDP) crystals were characterized by PXRD, FTIR, FT-RAMAN, NLO, Dielectric studies.