One-step synthesis of van der Waals heterostructures of graphene and two-dimensional superconducting α- M o2 C

Assembling different two-dimensional (2D) crystals, covering a very broad range of properties, into van der Waals (vdW) heterostructures enables unprecedented possibilities for combining the best of different ingredients in one objective material. So far, metallic, semiconducting, and insulating 2D crystals have been used successfully in making functional vdW heterostructures with properties by design. Here, we expand 2D superconducting crystals as a building block of vdW hererostructures. One-step growth of large-scale high-quality vdW heterostructures of graphene and 2D superconducting α-Mo2C by using chemical vapor deposition is reported. The superconductivity and its 2D nature of the heterostructures are characterized by our scanning tunneling microscopy measurements. This adds 2D superconductivity, the most attractive property of condensed matter physics, to vdW heterostructures.