Domain Dynamics in Piezoresponse Force Microscopy: Quantitative Deconvolution and Hysteresis Loop Fine Structure

TL;DR

This paper develops an analytical model for Piezoresponse Force Spectroscopy signals, enabling quantitative deconvolution of domain dynamics and revealing nanoscale Barkhausen jumps related to defect interactions.

Contribution

It introduces a new analytical theory for PFS signals from arbitrary domain shapes and applies it to experimental data, uncovering detailed domain evolution and defect interactions.

Findings

Oblate domain formation during nucleation

Hysteresis loop fine structure linked to domain jumps

Strong domain-defect interactions observed

Abstract

Domain dynamics in the Piezoresponse Force Spectroscopy (PFS) experiment is studied using the combination of local hysteresis loop acquisition with simultaneous domain imaging. The analytical theory for PFS signal from domain of arbitrary cross-section is developed and used for the analysis of experimental data on Pb(Zr,Ti)O3 polycrystalline films. The results suggest formation of oblate domain at early stage of the domain nucleation and growth, consistent with efficient screening of depolarization field within the material. The fine structure of the hysteresis loop is shown to be related to the observed jumps in the domain geometry during domain wall propagation (nanoscale Barkhausen jumps), indicative of strong domain-defect interactions.