Single Crystal Growth Optimization of Magnesium-Doped Lithium Niobate.

摘要

The purpose of the Phase 11 program entitled Single Crystal Growth Optimization of Magnesium-Doped Lithium Niobate was to optimize the growth of MgO:LiNbO3. The first step in this direction consisted of developing means and methods to accurately measure absorption losses (scattering loss methods were previously developed under a Phase I contract). It was known at the outset that very sensitive instrumentation would be required to allow measurements on small samples. The results of the measurements of both types of photon loss would then be used to optimize the molar concentration of MgO in LiNbO3 to achieve crystals with low loss as well as high photorefractive damage threshold. Highly sensitive scattering and absorption facilities were developed and used in the process of optimizing crystal growth. The ability to accurately and routinely measure these parameters has allowed us to understand variability in the growth process, determine growth parameters, and --most importantly--to observe that specific propagation and polarization directions are significantly less lossy than others. Studies were performed on the growth, poling, and resulting properties of MgO-doped lithium niobate. Both photorefractive damage threshold and NLO phase-matching temperature were observed to vary with MgO concentration. For one crystal doped with a high MgO concentration, it was impossible to induce measurable photorefractive damage. Lithium niobate (doped), Nonlinear optics, Crystal growth, Photorefractive effect, optical properties.