Piezoresponse Force Microscopy contrast in transversally isotropic material
corresponding to the case of c+ - c- domains in tetragonal ferroelectrics is
analyzed using Green's function theory by Felten et al. [J. Appl. Phys. 96, 563
(2004)]. A simplified expression for PFM signal as a linear combination of
relevant piezoelectric constant are obtained. This analysis is extended to
piezoelectric material of arbitrary symmetry with weak elastic and dielectric
anisotropies. This result provides a framework for interpretation of PFM
signals for systems with unknown or poorly known local elastic and dielectric
properties, including nanocrystalline materials, ferroelectric polymers, and
biopolymers.Comment: 20 pages, 3 figures, 1 table, accepted to Appl. Phys. Lett. (without
Appendices), algebraic errors were correcte