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arXiv · 2312.17652

Spin-orbit torques and magnetization switching in Gd/Fe multilayers generated by current injection in NiCu alloys

Federica Nasr·Federico Binda·Charles-Henri Lambert·Giacomo Sala·Paul Noël·Pietro Gambardella
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Abstract

Light transition metals have recently emerged as a sustainable material class for efficient spin-charge interconversion. We report measurements of current-induced spin-orbit torques generated by Ni$_{1-x}$Cu$_{x}$ alloys in perpendicularly magnetized ferrimagnetic Gd/Fe multilayers. We show that the spin-orbit torque efficiency of Ni$_{1-x}$Cu$_{x}$ increases with the Ni/Cu atomic ratio, reaching values comparable to those of Pt for Ni$_{55}$Cu$_{45}$. Furthermore, we demonstrate magnetization switching of a 20-nm-thick Gd/Fe multilayer with a threshold current that decreases with increasing Ni concentration, similar to the spin-orbit torque efficiency. Our findings show that Ni$_{1-x}$Cu$_{x}$$-$based magnetic heterostructures allow for efficient control of the magnetization by electric currents.

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Federica Nasr, Federico Binda, Charles-Henri Lambert, Giacomo Sala, Paul Noël, Pietro Gambardella. 2023-12-29. Spin-orbit torques and magnetization switching in Gd/Fe multilayers generated by current injection in NiCu alloys. https://doi.org/10.1063/5.0178878

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