Funct. Mater. 2014; 21 (2): 206-210.

http://dx.doi.org/10.15407/fm21.02.206

Theory of magnetization dynamics in a dual-free-layer spin-torque nano-oscillator with isotropic free layers

O.V.Prokopenko[1], V.S.Tiberkevich[2], A.N. Slavin[2]

[1] Faculty of Radiophysics, T.Shevchenko National University of Kyiv, 64/13 Volodymyrska Str., 01601 Kyiv, Ukraine
[2] Department of Physics, Oakland University, 2200 North Squirrel Rd., 48309 Rochester, MI, USA

Abstract: 

The analytical theory of magnetization dynamics in a dual-free-layer spin-torque nano-oscillator (DFL STNO) operating in the absence of a bias magnetic field is developed. The theory is based on a system of simplified dynamic equations written in collective variables and yields an analytic expression for the upper dc current density threshold of stable magnetization dynamics (generation) in the DFL STNO. This threshold is caused by a dipolar coupling between the free layers and can be controlled by choosing an appropriate geometry of the DFL STNO structure.

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