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arXiv · 2408.05759

A seamless graphene spin valve based on proximity to van der Waals magnet Cr$_2$Ge$_2$Te$_6$

Haozhe Yang·Marco Gobbi·Franz Herling·Van Tuong Pham·Francesco Calavalle·Beatriz Martín-García·Albert Fert·Luis E. Hueso·Fèlix Casanova
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Abstract

Pristine graphene is potentially an ideal medium to transport spin information. Proximity effects, where a neighbouring material is used to alter the properties of a material in adjacent (or proximitized) regions, can also be used in graphene to generate and detect spins by acquiring spin-orbit coupling or magnetic exchange coupling. However, the development of seamless spintronic devices that are based uniquely on proximity effects remains challenging. Here, we report a two-dimensional graphene spin valve that is enabled by proximity to the van der Waals magnet Cr$_2$Ge$_2$Te$_6$. Spin precession measurements show that graphene acquires both spin-orbit coupling and magnetic exchange coupling when interfaced with the Cr$_2$Ge$_2$Te$_6$. This leads to spin generation by both electrical spin injection and the spin Hall effect, while retaining long-distance spin transport. The simultaneous presence of spin-orbit coupling and magnetic exchange coupling also leads to a sizeable anomalous Hall effect.

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Haozhe Yang, Marco Gobbi, Franz Herling, Van Tuong Pham, Francesco Calavalle, Beatriz Martín-García, Albert Fert, Luis E. Hueso, Fèlix Casanova. 2024-08-11. A seamless graphene spin valve based on proximity to van der Waals magnet Cr$_2$Ge$_2$Te$_6$. https://doi.org/10.1038/s41928-024-01267-0

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