We report on experiments of spin filtering through ultra-thin single-crystal layers of the insulating and ferromagnetic oxide BiMnO3 (BMO). The spin polarization of the electrons tunneling from a gold electrode through BMO is analyzed with a counter-electrode of the half-metallic oxide La2/3Sr1/3MnO3 (LSMO). At 3 K we find a 50% change of the tunnel resistances according to whether the magnetizations of BMO and LSMO are parallel or opposite. This effect corresponds to a spin filtering effciency of up to 22%. Our results thus show the potential of complex ferromagnetic insulating oxides for spin filtering and injection.
@article{arxiv.cond-mat/0504667,
title = {Spin filtering through ferromagnetic BiMnO3 tunnel barriers},
author = {M. Gajek and M. Bibes and A. Barthelemy and K. Bouzehouane and S. Fusil and M. Varela and J. Fontcuberta and A. Fert},
journal= {arXiv preprint arXiv:cond-mat/0504667},
year = {2009}
}