Magnetic digital flop of ferroelectric domain with fixed spin chirality in a triangular lattice helimagnet

TL;DR

This study investigates how in-plane magnetic fields induce a 120-degree flop of electric polarization in a triangular-lattice helimagnet, revealing a fixed spin chirality during domain reorientation, with implications for magnetoelectric control.

Contribution

It demonstrates a magnetic field-induced 120-degree flop of electric polarization in a triangular-lattice helimagnet while preserving spin chirality, providing new insights into multiferroic domain control.

Findings

In-plane magnetic fields induce a 120-degree flop of electric polarization.

Spin chirality remains conserved during the polarization flop.

Magnetoelectric phase diagrams depend on magnetic field direction.

Abstract

Ferroelectric properties in magnetic fields of varying magnitude and direction have been investigated for a triangular-lattice helimagnet CuFe1-xGaxO2 (x=0.035). The magnetoelectric phase diagrams were deduced for magnetic fields along [001], [110], and [1-10] direction, and the in-plane magnetic field was found to induce the rearrangement of six possible multiferroic domains. Upon every 60-degree rotation of in-plane magnetic field around the c-axis, unique 120-degree flop of electric polarization occurs as a result of the switch of helical magnetic q-vector. The chirality of spin helix is always conserved upon the q-flop. The possible origin is discussed in the light of the stable structure of multiferroic domain wall.