| Autor: |
Guan, Y., Abraham, D. W., Gaidis, M. C., Hu, G., O’Sullivan, E. J., Nowak, J. J., Trouilloud, P. L., Worledge, D. C., Sun, J. Z. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; Apr2009, Vol. 105 Issue 7, p07D127-07D127-3, 3p, 3 Graphs |
| Abstrakt: |
We present room-temperature measurements of high-frequency magnetization fluctuation (mag noise) in MgO-based nanopillar magnetic tunnel junctions (MTJs) biased with a direct current (dc). In the frequency range of 1–13 GHz, double mag-noise peaks are observed for some MTJs while others only show a single mag-noise peak. The in-plane field dependence of the mag-noise peak frequency is consistent with the Kittel formula. For all MTJs measured, the bias-dependent shift in the mag-noise peak frequency has a pronounced asymmetry. In addition, we find nonmonotonic variations in peak linewidth as a function of the external in-plane magnetic field and of the dc bias current. These suggest the possible involvement of nonmacrospin modes in spin-torque-dependent thermal mag-noise generation. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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