Clamping of ferroelectric and ferromagnetic domain walls in conical spiral magnets

TL;DR

This paper investigates the structure and behavior of domain walls in multiferroic conical spiral magnets, revealing a transition from coupled to decoupled ferromagnetic and ferroelectric domain walls, with implications for switching phenomena.

Contribution

It introduces a simple spin model for conical spiral ground states and derives a continuum model describing domain wall behavior and the transition between coupled and decoupled regimes.

Findings

Identifies a transition from clamped to decoupled domain walls.

Derives a continuum model for spiral plane rotation at domain walls.

Discusses implications for switching in CoCr2O4.

Abstract

We study the structure of domain walls in multiferroic magnets with the conical spiral ordering. We formulate a simple spin model which has a conical spiral ground state in absence of magnetic anisotropies. We find a transition from the regime where ferromagnetic and ferroelectric domain walls are clamped to the regime where they are decoupled and derive a continuum model describing rotation of the spiral plane at the domain wall. The importance of these results for the switching phenomena observed in CoCr2O4 is discussed.