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arXiv · 0812.2509

Spin-Transfer Torque in Helical Spin-Density Waves

O. Wessely·B. Skubic·L. Nordstrom
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Abstract

The current driven magnetisation dynamics of a helical spin-density wave is investigated. Expressions for calculating the spin-transfer torque of real systems from first principles density functional theory are presented. These expressions are used for calculating the spin-transfer torque for the spin spirals of Er and fcc Fe at two different lattice volumes. It is shown that the calculated torque induces a rigid rotation of the order parameter with respect to the spin spiral axis. The torque is found to depend on the wave vector of the spin spiral and the spin-polarisation of the Fermi surface states. The resulting dynamics of the spin spiral is also discussed.

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O. Wessely, B. Skubic, L. Nordstrom. 2008-12-13. Spin-Transfer Torque in Helical Spin-Density Waves. https://doi.org/10.1103/physrevb.79.104433

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