Restrictive domain motion in polarization switching of lithium niobate

We investigate the electrostatic control of domain nucleation and motion for periodical polarization (Ps) switching on Z-cut congruent-grown lithium niobate (LiNbO3). A tenfold reduction in the tangential field (Ex) can be resolved as the perturbed, positive charge density intervening otherwise the single-domain crystal exceeds 10−3Ps. This concept is realized in a two-step procedure consisting of a high-temperature treatment followed by pulsed field poling. Bulk periodic polarization switching is then realized underneath the oxidized electrode with the lateral 180° domain motion confined to the edge of the charged domain boundary. The forward domain growth can extend through the 500-μm-thick substrate and reach an aspect ratio as large as 150. These observations are attributed to the constraint on domain nucleation and the suppression of Ex by the positive charge originating from the divergence of Ps at the inverted domain boundary near the subsurface regime.