Multiferroic and magnetoelectric materials – Developments and perspectives

¹ Angewandte Physik, Universität Duisburg-Essen, 47048 Duisburg, Germany
² Department of Chemistry, University of Liverpool, L69 7ZD Liverpool, U.K.
³ Institute of Materials Science, Duisburg-Essen University, 47141 Essen, Germany
⁴ School of Physics, NISER, IOP Campus, Bhubaneswar 751005, India

^a e-mail: wolfgang.kleemann@uni-due.de

Abstract

Multiferroic (MF) materials with simultaneous magnetic and electric long range order and occasionally, mutual magnetoelectric (ME) coupling, have recently attracted considerable interest. The small linear ME effect has been shown to control spintronic devices very efficiently, e.g. via the classic ME antiferromagnet Cr₂O₃ using exchange bias. Similar nano-engineering concepts exist also for type-I MF single phase materials, whose magnetic and polar orders have distinct origins like BiFeO₃. Strong ME coupling occurs in type-II multiferroics, where ferroelectricity is due to spiral spin order as in TbMnO3. Record high ME response coming close to applicability arises in stress-strain coupled multiphase magnetoelectrics such as PZT/FeBSiC composites. Higher order ME response in disordered systems (“type-III multiferroics”) extends the conventional MF scenario toward ME quantum paraelectric and multiglass materials with polarization-induced control of magnetic exchange, as e.g. in EuTiO₃, Sr_0.98Mn_0.02TiO₃, and PbFe_0.5Nb_0.5O₃.