Materials Contrast in Piezoresponse Force Microscopy

TL;DR

This paper develops a theoretical framework for interpreting Piezoresponse Force Microscopy signals in various piezoelectric materials, including complex and poorly characterized systems, by extending Green's function analysis to arbitrary symmetries.

Contribution

It extends existing Green's function analysis of PFM contrast to arbitrary symmetry piezoelectric materials with weak anisotropies, aiding interpretation of signals in complex systems.

Findings

Derived simplified PFM signal expressions for transversally isotropic materials.

Extended analysis to materials with arbitrary symmetry and weak anisotropies.

Provides a framework for interpreting PFM signals in nanocrystalline and biopolymer systems.

Abstract

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.