Interlayer coupling in van der Waals heterostructures exhibits unique physical properties and presents a new pathway for diverse applications in materials science and photonics. Interestingly, photo-responsivity of graphene with semiconducting transition metal dichalcogenide (TMD) can be enhanced in the UV-visible range by interlayer charge/energy transfer. However, such an effect has been studied only for semiconducting materials.
In this work, we will discuss ultrafast hot-electron transfer in atomically thin metallic-layer VSe2/graphene heterostructures investigated by time-resolved pump-probe spectroscopy. Our experimental finding extends the concepts of conventional two-dimensional heterostructures to metallic-layer and can provide a new degree of freedom for designing novel functionalized materials and devices.