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arXiv · 1001.5367

Spin-current vortices in current-perpendicular-to-plane nanoconstricted spin-valves

N. Strelkov·A. Vedyayev·N. Ryzhanova·D. Gusakova·L. D. Buda-Prejbeanu·M. Chshiev·S. Amara·N. de Mestier·C. Baraduc·B. Dieny
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Abstract

The charge and spin diffusion equations taking into account spin-flip and spin-transfer torque were numerically solved using a finite element method in complex non-collinear geometry with strongly inhomogeneous current flow. As an illustration, spin-dependent transport through a non-magnetic nanoconstriction separating two magnetic layers was investigated. Unexpected results such as vortices of spin-currents in the vicinity of the nanoconstriction were obtained. The angular variations of magnetoresistance and spin-transfer torque are strongly influenced by the structure geometry.

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N. Strelkov, A. Vedyayev, N. Ryzhanova, D. Gusakova, L. D. Buda-Prejbeanu, M. Chshiev, S. Amara, N. de Mestier, C. Baraduc, B. Dieny. 2011-07-13. Spin-current vortices in current-perpendicular-to-plane nanoconstricted spin-valves. https://doi.org/10.1103/physrevb.84.024416

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