Singe ferroelectric and chiral magnetic domain of single-crystalline BiFeO$_3$ in an electric field

TL;DR

This study demonstrates reversible control of ferroelectric and magnetic domains in single-crystalline BiFeO$_3$ using electric fields, achieving a monodomain state with potential for advanced multiferroics applications.

Contribution

It reveals the ability to switch and stabilize single-domain ferroelectric and chiral magnetic states in bulk BiFeO$_3$, surpassing thin film limitations.

Findings

Reversible switching of electric polarization directions.

Achievement of a ferroelectric monodomain with single-q spin spiral.

Potential for enhanced multiferroic device applications.

Abstract

We report polarized neutron scattering and piezoresponse force microscopy studies of millimeter-sized single crystals of multiferroic BiFeO$_3$. The crystals, grown below the Curie temperature, consist of a single ferroelectric domain. Two unique electric polarization directions, as well as the populations of equivalent spiral magnetic domains, can be switched reversibly by an electric field. A ferroelectric monodomain with a single-$q$ single-helicity spin spiral can be obtained. This level of control, so far unachievable in thin films, makes single-crystal BiFeO$_3$ a promising object for multiferroics research.