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arXiv · 2005.11058

Swapping Exchange and Spin-Orbit Coupling in 2D van der Waals Heterostructures

Klaus Zollner·Martin Gmitra·Jaroslav Fabian
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Abstract

The concept of swapping the two most important spin interactions -- exchange and spin-orbit coupling -- is proposed based on two-dimensional multilayer van der Waals heterostructures. Specifically, we show by performing realistic ab initio simulations, that a single device consisting of a bilayer graphene sandwiched by a 2D ferromagnet Cr$_2$Ge$_2$Te$_6$ (CGT) and a monolayer WS$_2$, is able not only to generate, but also to swap the two interactions. The highly efficient swapping is enabled by the interplay of gate-dependent layer polarization in bilayer graphene and short-range spin-orbit and exchange proximity effects affecting only the layers in contact with the sandwiching materials. We call these structures ex-so-tic, for supplying either exchange (ex) or spin-orbit (so) coupling in a single device, by gating. Such bifunctional devices demonstrate the potential of van der Waals spintronics engineering using 2D crystal multilayers.

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Klaus Zollner, Martin Gmitra, Jaroslav Fabian. 2020-05-22. Swapping Exchange and Spin-Orbit Coupling in 2D van der Waals Heterostructures. https://doi.org/10.1103/physrevlett.125.196402

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