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arXiv · 1410.3957

Micromagnetic Study of Spin Transfer driven Vortex Dipole and Vortex Quadrupole Dynamics

A. Giordano·V. Puliafito·L. Torres·M. Carpentieri·B. Azzerboni·G. Finocchio
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Abstract

Vortices and antivortices are typical non uniform magnetization configurations that can be achieved in spin-torque oscillators with in-plane materials. Dynamics of a vortex-antivortex pair, namely vortex dipole, were predicted and already observed. In this paper, we present a systematic micromagnetic study on that kind of dynamics in different spin-valves where the current is injected through a nano-aperture. Rotation and translation of vortex dipoles and rotation of vortex quadrupoles are shown depending on the shape and the size of the spin-valve. The origin of the different behaviors is explained within a micromagnetic framework.

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A. Giordano, V. Puliafito, L. Torres, M. Carpentieri, B. Azzerboni, G. Finocchio. 2014-10-15. Micromagnetic Study of Spin Transfer driven Vortex Dipole and Vortex Quadrupole Dynamics. https://doi.org/10.1109/tmag.2014.2323478

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