MnSb2O6: A polar magnet with a chiral crystal structure

TL;DR

This paper reports the discovery of a chiral magnetic structure in MnSb2O6, a polar magnet with a unique co-rotating cycloid arrangement stabilized by ab-initio calculations, and predicts its multiferroic behavior with a novel ferroelectric switching mechanism.

Contribution

It reveals a new magnetic ground state in MnSb2O6 involving co-rotating cycloids and links structural and magnetic chirality through vector chirality, supported by theoretical calculations.

Findings

Magnetic structure based on co-rotating cycloids

Coupling between structural and magnetic chirality via vector chirality

Predicted multiferroic behavior with a unique ferroelectric switching mechanism

Abstract

Structural and magnetic chiralities are found to coexist in a small group of materials in which they produce intriguing phenomenologies such as the recently discovered skyrmion phases. Here, we describe a previously unknown manifestation of this interplay in MnSb2O6, a trigonal oxide with a chiral crystal structure. Unlike all other known cases, the MnSb2O6 magnetic structure is based on co-rotating cycloids rather than helices. The coupling to the structural chirality is provided by a magnetic axial vector, related to the so-called vector chirality. We show that this unique arrangement is the magnetic ground state of the symmetric-exchange Hamiltonian, based on ab-initio theoretical calculations of the Heisenberg exchange interactions, and is stabilised by out-of-plane anisotropy. MnSb2O6 is predicted to be multiferroic with a unique ferroelectric switching mechanism.