Electric field control of magnetic properties and electron transport in BaTiO3-based multiferroic heterostructures. (27th November 2015)

• Record Type: Journal Article
• Authors: Asa, M; Baldrati, L; Rinaldi, C; Bertoli, S; Radaelli, G; Cantoni, M; Bertacco, R
• Is Part Of: Journal of physics. Volume 27:Number 50(2015)
• Publication Date: 2015-11-27
• Subjects: multiferroic heterostructure -- magnetoelectric coupling -- tunneling -- BaTiO3 -- antiferromagnetic -- interface -- magnetotransport; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/0953-8984/27/50/504004
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: In this paper, we report on a purely electric mechanism for achieving the electric control of the interfacial spin polarization and magnetoresistance in multiferroic tunneling junctions. We investigate micrometric devices based on the Co/Fe/BaTiO3 /La0.7 Sr0.3 MnO3 heterostructure, where Co/Fe and La0.7 Sr0.3 MnO3 are the magnetic electrodes and BaTiO3 acts both as a ferroelectric element and tunneling barrier. We show that, at 20 K, devices with a 2 nm thick BaTiO3 barrier present both tunneling electroresistance (TER = 12 ± 0.1%) and tunneling magnetoresistance (TMR). The latter depends on the direction of the BaTiO3 polarization, displaying a sizable change of the TMR from −0.32 ± 0.05% for the polarization pointing towards Fe, to −0.12 ± 0.05% for the opposite direction. This is consistent with the on-off switching of the Fe magnetization at the Fe/BaTiO3 interface, driven by the BaTiO3 polarization, we have previously demonstrated in x-ray magnetic circular dichroism experiments.