Towards room-temperature superconductivity in low-dimensional C60 nanoarrays: An ab initio study

Abstract

We propose to raise the critical temperature T-c for superconductivity in doped C-60 molecular crystals by increasing the electronic density of states at the Fermi level N(E-F) and thus the electron-phonon coupling constant in low-dimensional C-60 nanoarrays. We consider both electron and hole dopings and present numerical results for N(EF), which increases with the decreasing bandwidth of the partly filled h(u) - and t(1u) - derived frontier bands with the decreasing coordination number of C-60. Whereas a significant increase in N(E-F) occurs in two-dimensional (2D) arrays of doped C-60 intercalated in-between graphene layers, we propose that the highest-T-c values approaching room temperature may occur in bundles of nanotubes filled by one-dimensional (1D) arrays of externally doped C-60 or La@C-60 or in diluted three-dimensional (3D) crystalswhere quasi-1D arrangements of C-60 form percolation paths.