Spin-torque driven magnetic vortex self-oscillations in perpendicular magnetic fields

被引：27

作者：

Finocchio, G. ^{[1
,3
]}

Pribiag, V. S. ^{[2
]}

Torres, L. ^{[3
]}

Buhrman, R. A. ^{[2
]}

Azzerboni, B. ^{[1
]}

机构：

[1] Univ Messina, Dipartimento Fis Mat & Ingn Electtron, I-98166 Messina, Italy

[2] Cornell Univ, Ithaca, NY 14853 USA

[3] Univ Salamanca, Dept Fis Aplicada, E-37008 Salamanca, Spain

来源：

APPLIED PHYSICS LETTERS | 2010年 / 96卷 / 10期

基金：

美国国家科学基金会;

关键词：

POLARIZED CURRENT; MULTILAYERS;

D O I：

10.1063/1.3358387

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We have employed complete micromagnetic simulations to analyze dc current driven self-oscillations of a vortex core in a spin-valve nanopillar in a perpendicular field by including the coupled effect of the spin-torque and the magnetostatic field computed self-consistently for the entire spin-valve. The vortex in the thicker nanomagnet moves along a quasielliptical trajectory that expands with applied current, resulting in "blueshifting" of the frequency, while the magnetization of the thinner nanomagnet is nonuniform due to the bias current. The simulations explain the experimental magnetoresistance-field hysteresis loop and yield good agreement with the measured frequency versus current behavior of this spin-torque vortex oscillator. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3358387]

引用

页数：3

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