Tunnel magnetoresistance and robust room temperature exchange bias with multiferroic BiFeO3 epitaxial thin films

Hélène Béa (1) , Manuel Bibes (2) , Salia Cherifi (3) , Frithjof Nolting (4) , Bénédicte Warot-Fonrose (5) , Stéphane Fusil (1) , Gervasi Herranz (1) , Cyrile Deranlot (1) , Eric Jacquet (1) , Karim Bouzehouane (1) , Agnès Barthelemy (1)

1 Laboratoire Albert Fert (ex-UMPhy Unité mixte de physique CNRS/Thales)
2 IEF - Institut d'électronique fondamentale
3 LLN - Laboratoire Louis Néel
4 PSI - Paul Scherrer Institute
5 CEMES - Centre d'élaboration de matériaux et d'études structurales

The authors report on the functionalization of multiferroic BiFeO3 epitaxial films for spintronics. A first example is provided by the use of ultrathin layers of BiFeO3 as tunnel barriers in magnetic tunnel junctions with La2∕3Sr1∕3MnO3 and Co electrodes. In such structures, a positive tunnel magnetoresistance up to 30% is obtained at low temperature. A second example is the exploitation of the antiferromagnetic spin structure of a BiFeO3 film to induce a sizable (∼60Oe) exchange bias on a ferromagnetic film of CoFeB at room temperature. Remarkably, the exchange bias effect is robust upon magnetic field cycling, with no indications of training.

Mots clés: Multiferroics

Domaines: Autre [cond-mat.other]

Hélène Béa, Manuel Bibes, Salia Cherifi, Frithjof Nolting, Bénédicte Warot-Fonrose, et al.. Tunnel magnetoresistance and robust room temperature exchange bias with multiferroic BiFeO3 epitaxial thin films. Applied Physics Letters, 2006, Appl. Phys. Lett. 89, 242114 (2006). ⟨10.1063/1.2402204⟩. ⟨hal-00154487⟩