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Spin-Flip Scattering Effect on the Current-Induced Spin Torque in Ferromagnet-Insulator-Ferromagnet Tunnel Junctions

Zhen-Gang Zhu·Gang Su·Biao Jin·Qing-Rong Zheng
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Abstract

We have investigated the current-induced spin transfer torque of a ferromagnet-insulator-ferromagnet tunnel junction by taking the spin-flip scatterings into account. It is found that the spin-flip scattering can induce an additional spin torque, enhancing the maximum of the spin torque and giving rise to an angular shift compared to the case when the spin-flip scatterings are neglected. The effects of the molecular fields of the left and right ferromagnets on the spin torque are also studied. It is found that $τ^{Rx}/I_{e}$ ($τ^{Rx}$ is the spin-transfer torque acting on the right ferromagnet and $I_{e}$ is the tunneling elcetrical current) does vary with the molecular fields. At two certain angles, $τ^{Rx}/I_{e}$ is independent of the molecular field of the right ferromagnet, resulting in two crossing points in the curve of $τ^{Rx}/I_{e}$ versus the relevant orientation for different molecular fields.

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Zhen-Gang Zhu, Gang Su, Biao Jin, Qing-Rong Zheng. 2003-03-12. Spin-Flip Scattering Effect on the Current-Induced Spin Torque in Ferromagnet-Insulator-Ferromagnet Tunnel Junctions. https://doi.org/10.1016/s0375-9601(02)01597-9

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