Semi Organic Nlo Crystals

The present fascinating field of research is to synthesize, grow and characterize semi organic NLO crystals. Here an attempt has been made to synthesize and grow number of NLO semi organic crystals. The semi organic crystals posses both the good qualities of host organic material and additive-inorganic material. The crystals grown are amino acidγ-Glycine with additives namely, Potassium Nitrate, Sodium Nitrate, barium Nitrate, Ammonium Oxalate and Ammonium Chloride. Good crystals were obtained in a period of 3-4 weeks. Most of the crystals were transparent. The SHG efficiency has been tested by the Kurtz powder technique using Nd: YAG laser, and KDP sample has been used as a reference material. Since hardness play a key role in device fabrication and NLO materials are expected to play a major role in photonics as well as optical information processing, the present work pertains to mechanical characterization and SHG studies. The smooth surfaces of grown crystals were subjected to Vicker’s hardness for duration of 5-10seconds indentation time at room temperature. Load ranging from 5gms to 20gms were applied over a fixed interval of time. The micro hardness H and Mayer’s index n has been estimated. The value of Meyer’s index for various samples investigated falls below 1.6 suggests that crystals are hard or moderately soft. This behavior has increased with additives. Also, SHG efficiency for the grown crystals and laser damage threshold studies have been carried out using Q switched Nd: YAG laser for 10 nano seconds laser pulse width at a wavelength of 1064nm. The value obtained for laser damage threshold is due to lower/ moderate hardness seen by Vicker’s measurements. Plots of Hv, Mayer’s index n, as a function of load P, are shown graphically. PACS: 61.10, 78.30, 42.65 ky, 42.70 mp, 81.10 Dn, 61.72 Ss.