Ferromagnetism emerged from non-ferromagnetic atomic crystals

The isolation of graphene leads to a surge of interest in two dimensional materials, and recently, ferromagnetism has been observed in several two-dimensional materials. However, two-dimensional ferromagnetism remains rare. Here, Gong et al present an alternative approach to achieve two-dimensional ferromagnetism; combining antiferromagnetic FePS3 with non-magnetic WS2 they find a ferromagnetic state forms at the interface of these two materials. The recently emerged ferromagnetic two-dimensional (2D) materials provide unique platforms for compact spintronic devices down to the atomic-thin regime; however, the prospect is hindered by the limited number of ferromagnetic 2D materials discovered with limited choices of magnetic properties. If 2D antiferromagnetism could be converted to 2D ferromagnetism, the range of 2D magnets and their potential applications would be significantly broadened. Here, we discovered emergent ferromagnetism by interfacing non-magnetic WS2 layers with the antiferromagnetic FePS3. The WS2 exhibits an order of magnitude enhanced Zeeman effect with a saturated interfacial exchange field similar to 38 Tesla. Given the pristine FePS3 is an intralayer antiferromagnet, the prominent interfacial exchange field suggests the formation of ferromagnetic FePS3 at interface. Furthermore, the enhanced Zeeman effect in WS2 is found to exhibit a strong WS2-thickness dependence, highlighting the layer-tailorable interfacial exchange coupling in WS2-FePS3 heterostructures, which is potentially attributed to the thickness-dependent interfacial hybridization.

Automated summary

The isolation of graphene has sparked interest in two-dimensional materials, and recently, ferromagnetism has been observed in several. Gong et al. have found a ferromagnetic state at the interface of antiferromagnetic FePS3 and non-magnetic WS2, providing an alternative approach to achieve two-dimensional ferromagnetism.