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arXiv · 2209.11562

Magnetostatics of Room Temperature Compensated Co/Gd/Co/Gd-based Synthetic Ferrimagnets

Thomas J. Kools·Marnix C. van Gurp·Bert Koopmans·Reinoud Lavrijsen
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Abstract

Flexibility for interface engineering, and access to all-optical switching of the magnetization, make synthetic ferrimagnets an interesting candidate for advanced opto-spintronic devices. Moreover, due to their layered structure and disordered interfaces they also bear promise for the emerging field of graded magnetic materials. The fastest and most efficient spin-orbit torque driven manipulation of the magnetic order in this material system generally takes place at compensation. Here, we present a systematic experimental and modeling study of the conditions for magnetization compensation and perpendicular magnetic anisotropy in the synthetic ferrimagnetic Co/Gd/Co/Gd system. A model based on partial intermixing at the Co/Gd interfaces of this system has been developed which explains the experiments well, and provides a new tool to understand its magnetic characteristics. More specifically, this work provides new insight in the decay of the Co proximity-induced magnetization in the Gd, and the role the capping layer plays in the Gd magnetization.

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Thomas J. Kools, Marnix C. van Gurp, Bert Koopmans, Reinoud Lavrijsen. 2022-09-23. Magnetostatics of Room Temperature Compensated Co/Gd/Co/Gd-based Synthetic Ferrimagnets. https://doi.org/10.1063/5.0127694

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