Band structure of bilayer graphene intercalated by potassium atoms. Ab initio calculations

Using the electron density functional theory, the electronic band structure of pure and potassium-intercalated bilayer graphene has been studied. It is shown that after the intercalation process, a band gap appears in the band structure of bilayer graphene. In addition, the energy gap changes nonlinearly depending on the intercalate concentration in the interlayer space of bilayer graphene. We also calculated the energy spectra of bilayer graphene containing vacancy defects, the presence of which leads to the appearance of mid-gap states.