Room temperature ferromagnetism in Co-doped $\mathrm{Ce}{\mathrm{O}}_{2}$ films on Si(001)

Rapid Communication

Room temperature ferromagnetism in Co-doped $Ce O_{2}$ films on Si(001)

V. Fernandes, J. J. Klein, N. Mattoso, D. H. Mosca, E. Silveira, E. Ribeiro, W. H. Schreiner, J. Varalda, and A. J. A. de Oliveira

Phys. Rev. B 75, 121304(R) – Published 23 March 2007

Abstract

We investigate the room temperature ferromagnetism of nanocrystalline Co-doped $Ce O_{2}$ films electrodeposited onto Si(001) substrates. The nanocrystalline $Ce O_{2}$ films, containing from $0.5 to 13.2 at. %$ Co, present oxygen-vacancy formation with a considerable inclusion of Co into the lattice without evidence of metallic Co clusters or secondary phase formation. We correlate the robust ferromagnetism of this multifunctional magnetic oxide integrated on Si with two exchange mechanisms mediated by intrinsic defect centers observed in the emerging ferromagnetic insulators.