%0 Journal Article %K Manganese oxide %K Multiferroics %K Ferromagnetism %K exchange bias %K Ferromagnetic materials %K Heterojunctions %K Antiferromagnetic orderings %K Interfaces (materials) %K Critical thickness %K Exchange bias couplings %K Ferromagnets %K Interfacial exchanges %K Linear dichroism %A M Huijben %A P Yu %A L.W Martin %A H.J.A Molegraaf %A Y.-H Chu %A M.B Holcomb %A N Balke %A G Rijnders %A Ramamoorthy Ramesh %B Advanced Materials %D 2013 %G eng %P 4739-4745 %R 10.1002/adma.201300940 %T Ultrathin limit of exchange bias coupling at oxide multiferroic/ ferromagnetic interfaces %V 25 %X Exchange bias coupling at the multiferroic- ferromagnetic interface in BiFeO3/La0.7Sr0.3MnO3 heterostructures exhibits a critical thickness for ultrathin BiFeO3 layers of 5 unit cells (2 nm). Linear dichroism measurements demonstrate the dependence on the BiFeO3 layer thickness with a strong reduction for ultrathin layers, indicating diminished antiferromagnetic ordering that prevents interfacial exchange bias coupling. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.