We formed planar waveguides in LiNbO3 and LiTaO3 crystals by megaelectron volt He-ion implantation. The dark modes of both waveguides are measured and their refractive-index profiles are described according to the parameterized index profile reconstruction method. The extraordinary indices of both ion-implanted waveguides exhibit quite different profiles. We compare the thermal stability of barriers in ion-implanted LiNbO3 and LiTaO3 waveguides by annealing at different temperatures. The results show that the barrier in a LiTaO3 planar waveguide has higher thermal stability than that in a LiNbO3 waveguide. The experiments also show that annealing at a temperature higher than 400 °C results in recrystallization of the barrier.
© 1999 Optical Society of America
Original Manuscript: March 29, 1999
Published: August 20, 1999
Fei Lu, Feng Xiang Wang, Wei Li, Jian Hua Zhang, and Ke Ming Wang, "Annealing behavior of barriers in ion-implanted LiNbO3 and LiTaO3 planar waveguides," Appl. Opt. 38, 5122-5126 (1999)