Processing and characterization of improved congruent lithium niobate

Abstract

LiNbO3 exists in two forms: Most commercial devices are inexpensively fabricated from congruent melt that is ca. 1.5% off-stoichiometry. This produces devices of high optical quality for nonlinear optics but also high loss. Stoichiometric lithium niobate also exists, but in smaller more expensive specimens. Here we report the preparation and characterization of low-loss congruent samples. These are shown to be relatively free from extended defects.