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arXiv · 1908.06740

Magnetic Proximity Effect in a van der Waals Moiré Superlattice

Qingjun Tong·Mingxing Chen·Wang Yao
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Abstract

We investigate the magnetic proximity effect in van der Waals heterostructure formed by a monolayer semiconductor stacked on a 2D ferromagnet, where the lattice mismatch and twisting between the layers typically lead to the formation of moiré pattern. We find that the magnetic proximity effect arising from the spin dependent interlayer coupling depends sensitively on the interlayer atomic registry. Consequently, in the moiré pattern, the spatial variation of the atomic registry leads to a lateral modulation of magnetic proximity field. Such moiré modulated magnetic proximity effect manifests as a miniband spin splitting that strongly depends on the moiré periodicity which can be mechanically tuned by a relative twisting and/or strain between the layers. We also show, because of the moiré modulation on the interlayer distance, a perpendicular electric field can be used to control the miniband spin splitting. Our results suggest potential nanodevices where the moiré modulated magnetic proximity effect can lead to unique spin controllability.

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Qingjun Tong, Mingxing Chen, Wang Yao. 2019-08-19. Magnetic Proximity Effect in a van der Waals Moiré Superlattice. https://doi.org/10.1103/physrevapplied.12.024031

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