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arXiv · 2512.22726

Enabling high giant magnetoresistance in simple spin valves with ultrathin seed and free layers

Sachli Abdizadeh·Rachel E. Maizel·Dylan L. Haymore·Jing Zhao·F. Marc Michel·Satoru Emori
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Abstract

Emerging spin-orbit-torque devices based on spin valves require a thin magnetic free layer to maximize the torque per moment. However, reducing the free-layer thickness to $\lesssim 2$ nm deteriorates the giant magnetoresistance (GMR) signal for electrical readout. Here, we demonstrate that the addition of a 1-nm Cu seed layer promotes sharp interfaces in simple polycrystalline Co-based spin valves, enabling high GMR ratios of 5-7% at sub-2-nm free-layer thicknesses. Our work offers a pathway for engineering high-signal GMR readout in spin-orbit-torque digital memories and neuromorphic computers.

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Sachli Abdizadeh, Rachel E. Maizel, Dylan L. Haymore, Jing Zhao, F. Marc Michel, Satoru Emori. 2025-12-27. Enabling high giant magnetoresistance in simple spin valves with ultrathin seed and free layers. https://arxiv.org/abs/2512.22726

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