Atomic Scale Visualization of Dopant-Induced Unconventional Kondo Effect in Boron-doped graphene*

We describe the synthesis of large-area, highly-crystalline monolayer Boron-doped graphene (BG) sheets via atmospheric-pressure chemical vapor deposition, yielding unique and diverse B-doping site composed of substitutional Boron atoms and carbon vacancies. Scanning tunneling microscopy and spectroscopy (STM and STS) of BG reveal the presence of localized states in both the conduction and valence bands induced by Boron pz orbitals, confirmed by ab initio calculations. Furthermore, we demonstrate for the first time that atomic-resolved spin-polarization in a graphene sublattice via spectroscopic imaging of zero-energy states, induced by Boron incorporation. BG acts as a Kondo system with magnetic dopants embedded in C lattices, fully described by using the non-equilibrium Green's function method within the slave-boson mean-field approximation.