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arXiv · 2104.13007

A two-terminal spin valve device controlled by spin-orbit torques with enhanced giant magnetoresistance

Can Onur Avci·Charles-Henri Lambert·Giacomo Sala·Pietro Gambardella
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Abstract

We report on the combination of current-induced spin-orbit torques and giant magnetoresistance in a single device to achieve all-electrical write and read out of the magnetization. The device consists of perpendicularly magnetized TbCo and Co layers separated by a Pt or Cu spacer. Current injection through such layers exerts spin-orbit torques and switches the magnetization of the Co layer while the TbCo magnetization remains fixed. Subsequent current injection of lower amplitude senses the relative orientation of the magnetization of the Co and TbCo layers, which results in two distinct resistance levels for parallel and antiparallel alignment due to the current-in-plane giant magnetoresistance effect. We further show that the giant magnetoresistance of devices including a single TbCo/spacer/Co trilayer can be improved from 0.02% to 6% by using a Cu spacer instead of Pt. This type of devices offers an alternative route to a two terminal spintronic memory that can be fabricated with moderate effort.

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Can Onur Avci, Charles-Henri Lambert, Giacomo Sala, Pietro Gambardella. 2021-08-12. A two-terminal spin valve device controlled by spin-orbit torques with enhanced giant magnetoresistance. https://doi.org/10.1063/5.0055177

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