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arXiv · 0803.2871

Strong linewidth variation for spin-torque nano-oscillators as a function of in-plane magnetic field angle

K. V. Thadani·G. Finocchio·Z. -P. Li·O. Ozatay·J. C. Sankey·I. N. Krivorotov·Y. -T. Cui·R. A. Buhrman·D. C. Ralph
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Abstract

We measure the microwave signals produced by spin-torque-driven magnetization dynamics in patterned magnetic multilayer devices at room temperature, as a function of the angle of a magnetic field applied in the sample plane. We find strong variations in the frequency linewidth of the signals, with a decrease by more than a factor of 20 as the field is rotated from the magnetic easy axis to the in-plane hard axis. Based on micromagnetic simulations, we identify these variations as due to a transition from spatially incoherent to coherent precession.

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K. V. Thadani, G. Finocchio, Z. -P. Li, O. Ozatay, J. C. Sankey, I. N. Krivorotov, Y. -T. Cui, R. A. Buhrman, D. C. Ralph. 2008-03-19. Strong linewidth variation for spin-torque nano-oscillators as a function of in-plane magnetic field angle. https://doi.org/10.1103/physrevb.78.024409

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