  As a consequence of elasticity, mechanical deformations of crystals occur on
a length scale comparable to their thickness. This is exemplified by applying a
homogeneous electric field to a multi-domain ferroelectric crystal: as one
domain is expanding the adjacent ones are contracting, leading to clamping at
the domain boundaries. The piezomechanically driven surface corrugation of
micron-sized domain patterns in thick crystals using large-area top electrodes
is thus drastically suppressed, barely accessible by means of piezoresponse
force microscopy.
