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Title:Search for magnetoresistance in excess of 1000% in Ni point contacts: Density functional calculations
Authors:A. R. Rocha, T. Archer, and S. Sanvito, 2007
Abstract: Electronic transport in nickel magnetic point contacts is investigated with a combination of density functional theory and the nonequilibrium Green's function method in the linear response limit. In particular, we address the possibility of huge ballistic magnetoresistance in impurity-free point contacts and the effects of oxygen impurities. On-site corrections over the local spin density approximation for the exchange and correlation potential, namely, the LDA+U method, are applied in order to account for low coordination and strong correlations. We show that impurity-free point contacts present magnetoresistance never in excess of 50%. This value can raise up to about 450% in the case of oxygen contamination. These results suggest that magnetoresistance in excess of 1000% cannot have solely electronic origin.
ICHEC Project:Transport properties of organic macromolecules: modeling at the boundaries between biology and nano-electronics
Publication:Phys. Rev. B 76, 054435 (2007)
URL: http://link.aps.org/doi/10.1103/PhysRevB.76.054435
Keywords: density functional theory, exchange interactions (electron), Green's function methods, magnetoresistance, nickel, point contacts
Status: Published

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