Abstract

KTP is extensively used for frequency doubling of the Nd-based lasers operating between 1-2 μm. Recent progress in KTP crystal growth has made available crystals of increasing size. The finite walkoff angle in KTP may, however, limit applications with long interaction lengths as well as intracavity and resonator designs. It is well known that noncritic al phase-matching (NCPM) affords zero walk-off and broad bandwidth tolerances. Previous studies of NCPM second harmonic generation processes in KTP found particularly high temperature tolerances, with an observed bandwidth at 0.994. μm of 175°C cm for y-propagalion. Given these advantages, a KTP-related nonlinear crystal that can NC.PM the 1.064 μηι or the 1.32 μm lines of the Nd:YAG will be of great practical interest. We discuss here one approach to obtain such a material. By varying the composition variation of solid solution of KTP isomorphs, the birefringence and, therefore, NCPM wavelength can be tuned. Tire growth and characterization of the optimal solid solution crystals for this application are reported.

© 1993 Optical Society of America