*** 9801383 Ruderman This Small Business Innovation Research Phase 11 Project a new approach to the growth of single crystals of silver gallium sulfide (AgGaS2 or AGS) - a unique material for nonlinear optical applications. An AGS optical parametric oscillator that can be pumped by a 1.06 um Nd:YAG laser can provide radiation continuously tunable from 2.5 to 10 um. All present crystal growth methods for AGS use directional crystallization from a congruent melt, that produce as-grown crystals containing second phase inclusions that have to be annealed to improve their optical quality. This technology produces material of variable composition, yield, and quality, involves high cost and yields crystals of limited size, all of which limit potential applications of AGS. In our Phase I research and in a subsequent INRAD funded bridge program, we have established the feasibility of AGS crystal growth by Czochralski and Top Seeded Solution Growth (TSSG) Encapsulated by a Rotating Seal. In Phase II we propose to further develop these two new crystal growth processes. High quality AGS crystals of large size, high quality and lower cost will make possible efficient laser sources continuously tunable from 2.5 to 10 um. Such sources will have numerous commercial applications in environmental monitoring for contaminants in air, spectroscopy research, Microelectronics manufacturing and high resolution infrared spectrometers. ***
