Anti-ferromagnetic coupling in hybrid magnetic tunnel junctions mediated by monomolecular layers of α-sexithiophene

C. Blouzon (1) , F. Ott (2) , L. Tortech (3) , D. Fichou (3) , J.-B. Moussy (4)

1 UPMC - Université Pierre et Marie Curie - Paris 6 - UFR de Médecine Pierre et Marie Curie
2 LLB - UMR 12 - Laboratoire Léon Brillouin
3 IPCM - Institut Parisien de Chimie Moléculaire
4 LNO - Laboratoire Nano-Magnétisme et Oxydes

We report here on the magnetic coupling taking place between Fe3O4 and Co layers across an organic monolayer of α-sexithiophene (6T). The controlled growth of 6T ultrathin films on epitaxial Fe3O4 surfaces allows to prepare highly homogeneous insulating layers with thicknesses in the range 0.5–2.0 monolayers (ML). A combined study using vibrating sample magnetometry and polarized neutron reflectivity reveals that hybrid Fe3O4/6T/Co tunnel junctions show different magnetic couplings depending on the 6T thickness. In particular, magnetic coupling between Fe3O4 and Co layers separated by 1 ML of 6T is consistent with anti-ferromagnetic coupling, opening new perspectives for controlling magnetization in organic spintronic devices.

Domaines: Physique [physics]

C. Blouzon, F. Ott, L. Tortech, D. Fichou, J.-B. Moussy. Anti-ferromagnetic coupling in hybrid magnetic tunnel junctions mediated by monomolecular layers of α-sexithiophene. Applied Physics Letters, 2013, 103 (4), pp.042417. ⟨10.1063/1.4816954⟩. ⟨cea-01481044⟩