Evaluation of the internal field in lithium niobate ferroelectric domains by an interferometric method

We report on the evaluation of internal electric field of a ferroelectric engineered-domain in aLiNbO3 wafer crystal by detecting optical path length variation with a noninvasive interferometricinspection method. The lithium niobate wafer has been patterned and subjected to electric fieldpoling to obtain two antiparallel ferroelectric domains separated by a single domain wall. Thecrystal has been mounted into one arm of a Mach-Zehnder-type interferometerto study the phase map and evaluate the effects of domain reversion by a digitalholographic technique. Evaluation of the internal field and consequent variation of theelectro-optical properties of the different domains is analyzed.