Superconductivity at 28 K in CaB3C3 predicted from first-principles

The structural parameters, electronic properties, and superconducting state in the graphite-like BxC1-x intercalation compound, CaB3C3, have been studied using pseudopotential density functional theory within the generalized gradient approximation. Electronic and electron-phonon coupling calculations reveal that CaB3C3 is hole conducting and superconducting with critical temperature 28.2K, which is much higher than that of CaC6 (11.5K). The excellent superconducting state in CaB3C3 stems from the simultaneous presence of highly mobile and extremely confined conduction electrons, which enhances electron pairing and superconductivity. The current calculations might stimulate further theoretical and experimental investigation in search of new superconducting states in graphite-like BxC1-x intercalated compounds. (c) 2013 AIP Publishing LLC.