Bistable Coupling States Measured on Single Co Nanoclusters Deposited on CoO(111)

D. Le Roy , R. Morel , S. Pouget (1) , A. Brenac , L. Notin (2) , Thierry Crozes (3) , Wolfgang Wernsdorfer (4)

1 SPSMS - UMR 9001 - Service de Physique Statistique, Magnétisme et Supraconductivité
2 NM - Nanostructures et Magnétisme
3 NEEL - Nanofab - Nanofabrication
4 NEEL - QuantECA - Circuits électroniques quantiques Alpes

We describe novel features of the induced magnetic anisotropy in Co nanoclusters coupled with a CoO(111) layer. Individual cluster magnetism was studied using new microbridge superconducting quantum interference devices. Intrinsically, the Co clusters are single domains with an effective anisotropy constant K-F approximate to 1.5 x 10(6) erg . cm(-3). A bistable state of the ferromagnetic-antiferromagnetic coupling is revealed, with a maximum bias systematically observed along CoO[10 (1) over bar] and an interfacial coupling energy of 0.9 erg . cm(-2). The small bias observed in cluster assembly results from an averaging over the two opposite stable states.

Domaines: Physique [physics]

D. Le Roy, R. Morel, S. Pouget, A. Brenac, L. Notin, et al.. Bistable Coupling States Measured on Single Co Nanoclusters Deposited on CoO(111). Physical Review Letters, 2011, 107 (5), pp.057204. ⟨10.1103/PhysRevLett.107.057204⟩. ⟨hal-00976008⟩