1. Decoherence and Mode Hopping in a Magnetic Tunnel Junction Based Spin Torque Oscillator.
- Author
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Muduli, P. K., Heinonen, O. G., and Akerman, Johan
- Subjects
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TUNNEL junctions (Materials science) , *TORQUE , *MAGNETIZATION , *OSCILLATIONS , *COHERENCE (Optics) , *TIME-frequency analysis , *NONLINEAR statistical models - Abstract
We discuss the coherence of magnetic oscillations in a magnetic tunnel junction based spin torque oscillator as a function of the external field angle. Time-frequency analysis shows mode hopping between distinct oscillator modes, which arises from linear and nonlinear couplings in the Landau-Lifshitz-Gilbert equation, analogous to mode hopping observed in semiconductor ring lasers. These couplings and, therefore, mode hopping are minimized near the current threshold for the antiparallel alignment of free-layer with reference layer magnetization. Away from the antiparallel alignment, mode hopping limits oscillator coherence. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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