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arXiv · 1209.0655

Magnetic oscillations driven by the spin Hall effect in 3-terminal magnetic tunnel junction devices

Luqiao Liu·Chi-Feng Pai·D. C. Ralph·R. A. Buhrman
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Abstract

We show that direct current in a tantalum microstrip can induce steady-state magnetic oscillations in an adjacent nanomagnet through spin torque from the spin Hall effect (SHE). The oscillations are detected electrically via a magnetic tunnel junction (MTJ) contacting the nanomagnet. The oscillation frequency can be controlled using the MTJ bias to tune the magnetic anisotropy. In this 3-terminal device the SHE torque and the MTJ bias therefore provide independent controls of the oscillation amplitude and frequency, enabling new approaches for developing tunable spin torque nano-oscillators.

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Luqiao Liu, Chi-Feng Pai, D. C. Ralph, R. A. Buhrman. 2012-09-04. Magnetic oscillations driven by the spin Hall effect in 3-terminal magnetic tunnel junction devices. https://doi.org/10.1103/physrevlett.109.186602

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