Lateral Signals in Piezoresponse Force Microscopy at Domain Boundaries of Ferroelectric Crystals

TL;DR

This paper investigates the origins of lateral signals at domain boundaries in piezoresponse force microscopy of ferroelectric crystals, providing experimental data that challenges existing explanations and introduces new mechanisms.

Contribution

The study offers new experimental insights on lateral signals in PFM at ferroelectric domain boundaries and compares these findings with theoretical models, ruling out some previous explanations.

Findings

Certain explanations for lateral signals are invalidated by experimental data.

A new possible mechanism for lateral signals is proposed.

Quantitative comparison with models enhances understanding of the phenomenon.

Abstract

In piezoresponse force microscopy a lateral signal at the domain boundaries is occasionally observed. In recent years, a couple of experiments have been reported and varying explanations for the origin of this lateral signal have been proposed. Additionally, elaborated theoretical modeling for this particular issue has been carried out. Here we present experimental data obtained on different crystallographic cuts of $\rm LiNbO_3$, $\rm BaTiO_3$, and $\rm KTiOPO_4$ single crystals. We could thereby rule out some of the explanations proposed so far, introduce another possible mechanism, and quantitatively compare our results to the existing modeling.