Lattice-Rotation Vortex at the Charged Monoclinic Domain Boundary in a Relaxor Ferroelectric Crystal.

We present evidence of lattice-rotation vortices having an average radius of ∼7  nm at the ferroelectric domain boundary of (1-x)Pb(Zn_{1/3}Nb_{2/3})O_{3}-xPbTiO_{3} (x=0.08). Maps of crystal orientations and domain symmetry breaking are obtained using scanning convergent beam electron diffraction, which show fractional rotation vortices near the 50° monoclinic domain walls. The merging of 2D and 1D topological defects is consistent with inhomogeneous boundary charge and expected to have a large impact on the domain-switching mechanisms in relaxor ferroelectric crystals and ferroelectric devices.