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arXiv · 1503.03719

Chirp spectroscopy applied to the characterization of Ferromagnetic Resonance in Magnetic Tunnel Junctions

M. Ricci·P. Burrascano·M. Carpentieri·R. Tomasello·G. Finocchio
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Abstract

Magnetic Tunnel Junction devices find use in several applications based on the exploitation of the Spin-Transfer Torque phenomenon. The Ferromagnetic Resonance curve is a key characteristic of any Magnetic Tunnel Junctions. It is usually characterized both experimentally and numerically by performing a lot of measurements of the magnetic response to a sinusoidal field or current. Here we propose the use of a chirp signal as excitation signal to reconstruct the Ferromagnetic resonance curve with a single measurement/simulation. A micromagnetic comparison of the proposed method with the traditional one is shown.

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M. Ricci, P. Burrascano, M. Carpentieri, R. Tomasello, G. Finocchio. 2015-03-12. Chirp spectroscopy applied to the characterization of Ferromagnetic Resonance in Magnetic Tunnel Junctions. https://doi.org/10.1109/tmag.2014.2323269

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