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arXiv · 0810.1110

Auto-oscillation threshold and line narrowing in MgO-based spin-torque oscillators

S. Cornelissen·L. Bianchini·G. Hrkac·M. Op de Beeck·L. Lagae·Joo-Von Kim·T. Devolder·P. Crozat·C. Chappert·T. Schrefl
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Abstract

We present an experimental study of the power spectrum of current-driven magnetization oscillations in MgO tunnel junctions under low bias. We find the existence of narrow spectral lines, down to 8 MHz in width at a frequency of 10.7 GHz, for small applied fields with clear evidence of an auto-oscillation threshold. Micromagnetics simulations indicate that the excited mode corresponds to an edge mode of the synthetic antiferromagnet.

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S. Cornelissen, L. Bianchini, G. Hrkac, M. Op de Beeck, L. Lagae, Joo-Von Kim, T. Devolder, P. Crozat, C. Chappert, T. Schrefl. 2009-09-16. Auto-oscillation threshold and line narrowing in MgO-based spin-torque oscillators. https://doi.org/10.1209/0295-5075/87/57001

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