Characterization and manipulation of mixed phase domains in highly-strained BiFeO3 thin films

TL;DR

This study investigates the structural and polarization properties of mixed phase nanodomains in highly-strained BiFeO3 thin films, revealing their manipulation and implications for enhanced electromechanical responses.

Contribution

It identifies eight variants of mixed phase nanodomains and demonstrates deterministic control over their motion using scanning probe techniques.

Findings

Eight structural variants of MPNs identified

Polarization configurations mapped within MPNs

Deterministic manipulation of MPNs achieved

Abstract

The novel strain-driven morphotropic phase boundary (MPB) in highly-strained BiFeO3 thin film is featured by ordered mixed phase nanodomains (MPNs). Through scanning probe microscopy and synchrotron X-ray diffraction, eight structural variants of the MPNs are identified. Detailed polarization configurations within the MPNs are resolved using angular-dependent piezoelectric force microscopy. Guided by the obtained results, deterministic manipulation of the MPNs has been demonstrated by controlling the motion of the local probe. These findings are important for in-depth understanding of the ultrahigh electromechanical response arising from phase transformation between competing phases, enabling future explorations on the electronic structure, magnetoelectricity and other functionalities in this new MPB system.