Local Polarization Switching in the Presence of Surface Charged Defects: Microscopic Mechanisms and Piezoresponse Force Spectroscopy Observations

TL;DR

This paper investigates how surface charged defects influence local polarization switching in ferroelectric materials using analytical, numerical, and experimental Piezoresponse Force Microscopy techniques, revealing defect signatures and a universal deconvolution approach.

Contribution

It introduces a novel methodology for deconvolving PFM data to extract defect parameters, advancing understanding of defect-driven polarization switching at the microscopic level.

Findings

Defects significantly alter hysteresis loop structures.

The proposed deconvolution method accurately extracts defect parameters.

Surface charge defects impact switching behavior in ferroelectrics.

Abstract

The thermodynamics and kinetics of tip-induced polarization switching in Piezoresponse Force Microscopy in the presence of surface charge defects is studied using the combination of analytical and numerical techniques. The signature of the defects in hysteresis loop fine structure and Switching Spectroscopy PFM images is identified and compared to experimental observations. An approach for the deconvolution of PFM spectroscopy measurements to extract relevant defect parameters is derived. This methodology is universal and can be extended to switching in other ferroics and in reversible electrochemical processes, establishing a pathway for the understanding of the thermodynamics and kinetics of phase transitions at a single defect level.