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arXiv · 1103.3207

Spin-Torque Diode Measurements of MgO-Based Magnetic Tunnel Junctions with Asymmetric Electrodes

R. Matsumoto·A. Chanthbouala·J. Grollier·V. Cros·A. Fert·K. Nishimura·Y. Nagamine·H. Maehara·K. Tsunekawa·A. Fukushima·S. Yuasa
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Abstract

We present a detailed study of the spin-torque diode effect in CoFeB/MgO/CoFe/NiFe magnetic tunnel junctions. From the evolution of the resonance frequency with magnetic field at different angles, we clearly identify the free-layer mode and find an excellent agreement with simulations by taking into account several terms for magnetic anisotropy. Moreover, we demonstrate the large contribution of the out-of-plane torque in our junctions with asymmetric electrodes compared to the in-plane torque. Consequently, we provide a way to enhance the sensitivity of these devices for the detection of microwave frequency.

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R. Matsumoto, A. Chanthbouala, J. Grollier, V. Cros, A. Fert, K. Nishimura, Y. Nagamine, H. Maehara, K. Tsunekawa, A. Fukushima, S. Yuasa. 2011-03-16. Spin-Torque Diode Measurements of MgO-Based Magnetic Tunnel Junctions with Asymmetric Electrodes. https://doi.org/10.1143/apex.4.063001

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