The Dynamics of Coupled Spin-Torque Nano Oscillators: An Initial Exploration

  • J. Turtle
  • A. PalaciosEmail author
  • V. In
  • P. Longhini
Part of the Understanding Complex Systems book series (UCS)


In this work we explore the use of Spin Torque Nano Oscillators (STNOs) to produce a spintronics voltage oscillator in the microwave range. STNOs are quite small—on the order of 10 nm—and frequency agile. However, experimental results to date have produced power outputs that are too small to be viable. We attempt to increase power output by investigating the dynamics of a system of electrically-coupled STNOs. To set the foundation for further analysis, we consider both Spherical and Complex Stereographic coordinates for the Landau-Lifshitz-Gilbert Equation with spin torque term. Both coordinate systems effectively reduce the equation of a single STNO from three dimensions to two. Further, the Complex Stereographic representation transforms the equation into a nearly polynomial form that may prove useful for advanced dynamics analysis. Qualitative bifurcation diagrams show a rich set of behaviors in the parallel and series coupled systems and serve to develop intuition in system dynamics.


Free Layer Voltage Oscillator Center Manifold Reduction Spin Transfer Torque Tunable Frequency Range 
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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.San Diego State UniversitySan DiegoUSA

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