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arXiv · 1107.0867

Parametric oscillator based on non-linear vortex dynamics in low resistance magnetic tunnel junctions

S. Martin·N. de Mestier·C. Thirion·C. Hoarau·Y. Conraux·C. Baraduc·B. Diény
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Abstract

Radiofrequency vortex spin-transfer oscillators based on magnetic tunnel junctions with very low resistance area product were investigated. A high power of excitations has been obtained characterized by a power spectral density containing a very sharp peak at the fundamental frequency and a series of harmonics. The observed behaviour is ascribed to the combined effect of spin transfer torque and Oersted-Amp\`ere field generated by the large applied dc-current. We furthermore show that the synchronization of a vortex oscillation by applying a ac bias current is mostly efficient when the external frequency is twice the oscillator fundamental frequency. This result is interpreted in terms of a parametric oscillator.

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S. Martin, N. de Mestier, C. Thirion, C. Hoarau, Y. Conraux, C. Baraduc, B. Diény. 2011-07-05. Parametric oscillator based on non-linear vortex dynamics in low resistance magnetic tunnel junctions. https://doi.org/10.1103/physrevb.84.144434

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