Structural, dielectric and Raman spectroscopic study of complex electric and magnetic interactions in multiferroic ionic crystals

Holger Gibhardt,Fabian Ziegler,Götz Eckold

doi:10.1255/sew.2021.a22

Abstract

Holger Gibhardt, Fabian Ziegler and Götz Eckold tell us about the use of Raman spectroscopy to understand complex electric and magnetic interactions in multiferroic ionic crystals. Multiferroics are a relatively new class of materials that exhibit magnetic and electrical ordering simultaneously. Both phenomena are coupled so that electric forces may be used to control the magnetic structure and vice versa. Raman enables understanding of the underlying processes on the atomic level, essential for the development of new materials with these properties.

Highlights

While ordinary materials are usually either magnetically or electrically ordered, a relatively new class of materials of so-called multiferroics has been discovered that exhibits magnetic and electrical ordering simultaneously
Since the exact mechanism of spin coupling with the movement of ions and the resulting electric dipole moment is still not fully understood, detailed experimental and theoretical studies are needed which require advanced techniques like high-resolution
The stabilising interactions between different spins are mediated by the diamagnetic oxygen ions by the magnetic super-exchange

Summary

Introduction

While ordinary materials are usually either magnetically or electrically ordered, a relatively new class of materials of so-called multiferroics has been discovered that exhibits magnetic and electrical (and eventually mechanical) ordering simultaneously. The unique and fascinating feature of these systems is that both phenomena are coupled and that electric forces may be used to control the magnetic structure and vice versa. Most systems that have been investigated so far exhibit these extraordinary properties only at low temperatures. In view of possible applications in information technology, sensor technology etc., it is, a crucial task to increase the temperature range of multiferroics. Since the exact mechanism of spin coupling with the movement of ions and the resulting electric dipole moment is still not fully understood, detailed experimental and theoretical studies are needed which require advanced techniques like high-resolution

Published under a Creative Commons BY licence

Raman spectroscopy