A study on proton-exchanged and heat-treated LiNbO3 crystals by means of Raman and infrared spectrum

摘要

A study on LiNbO3 single-crystal samples obtained by different treatments has been performed by means of Raman and Infrared spectra. Raman scattering spectra show that some modes not only couple each other but also exchange intensities. Two characteristic absorption peaks at 2840 and 2920 cm(-1) in Infrared transmission spectra have been found. The results may be attributed to the changes of LiNbO3 microstructure and the coexistence of two possible phases formed by proton exchange and quick heat treatments, and to the existence of an internal strain induced by the nonuniform thermal expansion during the heat treatment process at high temperature. (c) 2006 Elsevier B.V. All rights reserved.