Domain dynamics in stoichiometric lithium tantalate revealed by wet etching and on-line second harmonic generation

The effect of chemical etching on the stability of domains in periodically poled stoichiometric lithium tantalate is studied by on-line second harmonic generation and microscopy. It is found that wet etching directly after poling leads to domain-wall movement, resulting in back-switching or domain merging. Head-to-head domains tend to backswitch, while tail-to-tail domains merge. For samples where the domain structure stabilized for longer time, no domain motion is observed when etched.