The insulator-metal transition of alkali-metal-doped fullerene

Quantum many-body interactions trigger new and unexpected emergent phenomena, such as superconductivity and magnetism, even in weak correlation materials, as recently exploited in twisted bilayer graphene. One classical example is superconductivity in Alkali-doped fullerides (e.g. K₃C₆₀) where conventional BCS theory and unconventional Mott physics meet. Despite a large number of works, the origin and the detailed mechanism of such a state remain still elusive. Here, by using angle-resolved photoemission spectroscopy on fullerene films grown on Bi₂Se₃ substrate, we study the insulator-metal transition derived by doping. With a controllable potassium doping mechanism, doping dependence of the electronic band structures is investigated.