Interferometric measurement of the internal field of lithium niobate without high-voltage electric field poling

A simple interferometric technique for measurement of the internal field (IF) in a ferroelectric crystal has been proposed. This technique has several advantages over the other methods used previously for evaluation of IFs in ferroelectric crystals. Here, the electro-optic property of lithium niobate is exploited for quantitative analysis of its IF. The strength of IF obtained using this technique lies within the range given in the literature. However, at frustrated domain inversion state, the measured value of IF shows a reduced value. A possible reason for this reduction based on the defect model has been discussed. (C) 2014 Society of Photo-Optical Instrumentation Engineers (SPIE)