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arXiv · 2104.09184

Large-area van der Waals epitaxy and magnetic characterization of Fe$_3$GeTe$_2$ films on graphene

J. Marcelo J. Lopes·Dietmar Czubak·Eugenio Zallo·Adriana I. Figueroa·Charles Guillemard·Manuel Valvidares·Juan Rubio Zuazo·Jesús López-Sanchéz·Sergio O. Valenzuela·Michael Hanke·Manfred Ramsteiner
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Abstract

Scalable fabrication of magnetic 2D materials and heterostructures constitutes a crucial step for scaling down current spintronic devices and the development of novel spintronic applications. Here, we report on van der Waals (vdW) epitaxy of the layered magnetic metal Fe$_3$GeTe$_2$ - a 2D crystal with highly tunable properties and a high prospect for room temperature ferromagnetism - directly on graphene by employing molecular beam epitaxy. Morphological and structural characterization confirmed the realization of large-area, continuous Fe$_3$GeTe$_2$/graphene heterostructure films with stable interfaces and good crystalline quality. Furthermore, magneto-transport and X-ray magnetic circular dichroism investigations confirmed a robust out-of-plane ferromagnetism in the layers, comparable to state-of-the-art exfoliated flakes from bulk crystals. These results are highly relevant for further research on wafer-scale growth of vdW heterostructures combining Fe$_3$GeTe$_2$ with other layered crystals such as transition metal dichalcogenides for the realization of multifunctional, atomically thin devices.

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J. Marcelo J. Lopes, Dietmar Czubak, Eugenio Zallo, Adriana I. Figueroa, Charles Guillemard, Manuel Valvidares, Juan Rubio Zuazo, Jesús López-Sanchéz, Sergio O. Valenzuela, Michael Hanke, Manfred Ramsteiner. 2021-04-19. Large-area van der Waals epitaxy and magnetic characterization of Fe$_3$GeTe$_2$ films on graphene. https://doi.org/10.1088/2053-1583%2Fac171d

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