Domain wall creep in epitaxial ferroelectric Pb(Zr0.2Ti0.8)O3 thin films

TL;DR

This study investigates the nanoscale domain dynamics and creep behavior of ferroelectric domain walls in epitaxial Pb(Zr0.2Ti0.8)O3 thin films using atomic force microscopy, revealing a two-step growth mechanism and disorder-induced creep motion.

Contribution

It provides new insights into the domain wall creep process and the role of disorder in epitaxial ferroelectric thin films.

Findings

Domain growth occurs via nucleation and radial wall motion.

Domain wall velocity follows a creep law with critical exponent near 1.

Disorder in the film influences the creep behavior.

Abstract

Ferroelectric switching and nanoscale domain dynamics were investigated using atomic force microscopy on monocrystalline Pb(Zr0.2Ti0.8)O3 thin films. Measurements of domain size versus writing time reveal a two-step domain growth mechanism, in which initial nucleation is followed by radial domain wall motion perpendicular to the polarization direction. The electric field dependence of the domain wall velocity demonstrates that domain wall motion in ferroelectric thin films is a creep process, with the critical exponent mu close to 1. The dimensionality of the films suggests that disorder is at the origin of the observed creep behavior.