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arXiv · 0909.2711

Critical current density for spin transfer torque switching with composite free layer structure

Chun-Yeol You
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Abstract

Critical current density of composite free layer (CFL) in magnetic tunneling junction is investigated. CFL consists of two exchange coupled ferromagnetic layers, where the coupling is parallel or anti-parallel. Instability condition of the CFL under the spin transfer torque, which is related with critical current density, is obtained by analytic spin wave excitation model and confirmed by macro-spin Landau-Lifshitz-Gilbert equation. The critical current densities for the coupled two identical layers are investigated with various coupling strengths, and spin transfer torque efficiencies.

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BibTeXRIS

Chun-Yeol You. 2009-09-15. Critical current density for spin transfer torque switching with composite free layer structure. https://doi.org/10.1016/j.cap.2009.11.079

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