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arXiv · 0902.1150

Spin torque from tunneling through impurities in a magnetic tunnel junction

Turan Birol·Piet W. Brouwer
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Abstract

We calculate the contribution to the spin transfer torque from sequential tunneling through impurities in a magnetic tunnel junction. For a junction with weakly polarized ferromagnetic contacts, the torque is found to be in the plane spanned by the magnetizations of the ferromagnetic contacts and proportional to $\sin θ$, where $θ$ is the angle between the magnetic moments. If the polarization is larger, the torque acquires a significant out-of-plane component and a different dependence on $θ$.

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Turan Birol, Piet W. Brouwer. 2009-07-31. Spin torque from tunneling through impurities in a magnetic tunnel junction. https://doi.org/10.1103/physrevb.80.014434

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