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arXiv · 1009.4296

Optimal control of magnetization dynamics in ferromagnetic heterostructures by spin--polarized currents

M. Wenin·A. Windisch·W. Poetz
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Abstract

We study the switching-process of the magnetization in a ferromagnetic-normal-metal multilayer system by a spin polarized electrical current via the spin transfer torque. We use a spin drift-diffusion equation (SDDE) and the Landau-Lifshitz-Gilbert equation (LLGE) to capture the coupled dynamics of the spin density and the magnetization dynamic of the heterostructure. Deriving a fully analytic solution of the stationary SDDE we obtain an accurate, robust, and fast self-consistent model for the spin-distribution and spin transfer torque inside general ferromagnetic/normal metal heterostructures. Using optimal control theory we explore the switching and back-switching process of the analyzer magnetization in a seven-layer system. Starting from a Gaussian, we identify a unified current pulse profile which accomplishes both processes within a specified switching time.

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M. Wenin, A. Windisch, W. Poetz. 2010-10-06. Optimal control of magnetization dynamics in ferromagnetic heterostructures by spin--polarized currents. https://doi.org/10.1063/1.3514070

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