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arXiv · 1504.02806

Enhancement of the Anti-Damping Spin Torque Efficacy of Platinum by Interface Modification

Minh-Hai Nguyen·Chi-Feng Pai·Kayla X. Nguyen·David A. Muller·Daniel C. Ralph·Robert A. Buhrman
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Abstract

We report a strong enhancement of the efficacy of the spin Hall effect (SHE) of Pt for exerting anti-damping spin torque on an adjacent ferromagnetic layer by the insertion of $\approx$ 0.5 nm layer of Hf between a Pt film and a thin, < 2 nm, Fe$_{60}$Co$_{20}$B$_{20}$ ferromagnetic layer. This enhancement is quantified by measurement of the switching current density when the ferromagnetic layer is the free electrode in a magnetic tunnel junction. The results are explained as the suppression of spin pumping through a substantial decrease in the effective spin-mixing conductance of the interface, but without a concomitant reduction of the ferromagnet\' s absorption of the SHE generated spin current.

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Minh-Hai Nguyen, Chi-Feng Pai, Kayla X. Nguyen, David A. Muller, Daniel C. Ralph, Robert A. Buhrman. 2015-04-10. Enhancement of the Anti-Damping Spin Torque Efficacy of Platinum by Interface Modification. https://doi.org/10.1063/1.4922084

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