Doping of C 60 -induced electronic states in BN nanopeapods: Ab initio simulations

We report the results of ab initio simulations of the electronic properties of a chain of ${\text{C}}_{60}$ molecules encapsulated in a boron-nitride nanotube\char22{}so-called BN nanopeapod. It is demonstrated that this structure can be effectively doped by depositing potassium atoms on the external wall of the BN nanotube. The resulting material becomes a true metallic one-dimensional crystal, where the conduction states are formed solely by the fullerene chain. At the doping rate of one K atom per ${\text{C}}_{60}$ molecule, the system shows the density of states at the Fermi level considerably higher than in any of the fullerene crystals presently made. This makes the doped BN-peapod structure an interesting candidate to study a possible superconducting state.