Spin-transfer torque in magnetic tunnel junctions: Scattering theory

@article{Xiao2008SpintransferTI,
  title={Spin-transfer torque in magnetic tunnel junctions: Scattering theory},
  author={Jiang Xiao and Gerrit E. W. Bauer and Arne Brataas},
  journal={Physical Review B},
  year={2008},
  volume={77},
  pages={224419}
}
We study the bias-dependent spin-transfer torque in magnetic tunnel junctions in the Stoner model by scattering theory. We show that the in-plane (Slonczewski type) torque vanishes and subsequently reverses its direction when the bias voltage becomes larger or the barrier wider than material and device-dependent critical values. We are able to reproduce the magnitude and the bias dependence of measured in-plane and out-of-plane torques using realistic parameters. The condition for the vanishing… 
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