Structural phase transformations of proton-exchanged layers of lithium niobate during annealing

摘要

Kinetics of phase transitions in the surface layer of proton-exchanged planar waveguides on X-cut of lithium niobate crystal during annealing at 330, 350, and 370 degrees C was investigated by optical methods (dark field microscopy, crossed-polarizers bright field microscopy, and mode spectroscopy). Nucleation and growth stages of phase transformations were identified. Based on mode spectroscopy data and analysis of previous works, we assume that transformation of (2)-phase into (1)-phase and further transformation into -phase were observed during experiment.