Abstract
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.
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Turtle, J., Palacios, A., In, V., Longhini, P. (2014). The Dynamics of Coupled Spin-Torque Nano Oscillators: An Initial Exploration. In: In, V., Palacios, A., Longhini, P. (eds) International Conference on Theory and Application in Nonlinear Dynamics (ICAND 2012). Understanding Complex Systems. Springer, Cham. https://doi.org/10.1007/978-3-319-02925-2_25
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DOI: https://doi.org/10.1007/978-3-319-02925-2_25
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