Watching Domains Grow: In-situ studies of polarization switching by combined Scanning Probe and Scanning Transmission Electron Microscopy

TL;DR

This study directly visualizes ferroelectric domain nucleation and growth in BiFeO3 films using combined scanning probe and transmission electron microscopy, revealing mesoscopic switching mechanisms crucial for multiferroic material functionality.

Contribution

It provides in-situ, spatially-resolved insights into domain dynamics and interactions in multiferroic materials, integrating experimental observations with phase-field modeling.

Findings

Preferential nucleation sites identified

Direction-dependent domain wall pinning observed

Metastable switching kinetics characterized

Abstract

Ferroelectric domain nucleation and growth in multiferroic BiFeO3 films is observed directly by applying a local electric field with a conductive tip inside a scanning transmission electron microscope. The nucleation and growth of a ferroelastic domain and its interaction with pre-existing 71^{\circ} domain walls are observed and compared with the results of phase-field modeling. In particular, a preferential nucleation site and direction-dependent pinning of domain walls is observed due to slow kinetics of metastable switching in the sample without a bottom electrode. These in-situ spatially-resolved observations of a first-order bias-induced phase transition reveal the mesoscopic mechanisms underpinning functionality of a wide range of multiferroic materials.