5 research outputs found
Current induced switching of magnetic domains to a perpendicular configuration
In a ferromagnet--normal-metal--ferromagnet trilayer, a current flowing
perpendicularly to the layers creates a torque on the magnetic moments of the
ferromagnets. When one of the contacts is superconducting, the torque not only
favors parallel or antiparallel alignment of the magnetic moments, as is the
case for two normal contacts, but can also favor a configuration where the two
moments are perpendicular. In addition, whereas the conductance for parallel
and antiparallel magnetic moments is the same, signalling the absence of giant
magnetoresistance in the usual sense, the conductance is greater in the
perpendicular configuration. Thus, a negative magnetoconductance is predicted,
in contrast with the usual giant magnetoresistance.Comment: 4 pages, 3 figures, major rewriting of the technical par
Seasonality of Mansonia titillans during dam construction, Biritiba-Mirim, São Paulo State, Brazil
Enhancement of giant magnetoresistance due to spin mixing in magnetic multilayers with a superconducting contact
We study the giant magnetoresistance (GMR) ratio in magnetic multilayers wit a single superconducting contact in the presence of spin-mixing processes. It has been recently shown [F. Taddei, S. Sanvito, J.H. Jefferson, and C. J. Lambert, Phys, Rev. Lett, 82, 4938 (1999)] that the GMR ratio of magnetic multilayers is strongly suppressed by the presence of a super conducting contact when spin flipping is not allowed. In this paper we demonstrate that the GMR ratio can be dramatically enhanced by spin-orbit interaction and/or noncollinear magnetic moments. The system is described using a tight-binding model with either s-p-d or s-d atomic orbitals per site