Crack tip domain switching in a ferroelectric single crystal under alternating electric fields

This paper presents in situ observations of domain switching near a crack tip in a poled 0.62PbMg1/3Mg2/3O3–0.38PbTiO3 single crystal under alternating electric fields by polarized light microscopy. Only 90° domain switching is observed under the field anti-parallel to the poling direction of the specimen. Upon the reversal of the field, the switched domains recover, both before and behind the crack tip. However, the electric field inducing 90° domain switching is much larger than that stimulating reverse domain switching.