Structural and electronic inhomogeneity of graphene revealed by Nano-ARPES

Abstract : Electronic structure describes the distribution of electronic states in reciprocal space, being one of the most fundamental concepts in condensed matter physics, since it determines the electrical, optical and magnetic behaviours of materials. Due to its two-dimensional honeycomb lattice with covalent bonding, pristine graphene exhibits unsurpassed in-plane stiffness and stable structural properties. Here by employing angle-resolved photoemission spectroscopy with spatial resolution ∼ 100 nm (Nano-ARPES), we discuss in detail the structural and electronic properties of graphene grown on cooper by chemical vapour deposition (CVD). Our results reveal the spatial inhomogeneity of graphene film, demonstrating the power of Nano-ARPES to detect the microscopic inhomogeneity of electronic structure for different materials.