Superconductivity in doped cubic silicon: an ab initio study

Abstract

We study within a first-principle approach the band structure, vibrational modes and electron-phonon coupling in boron, aluminum and phosphorus doped silicon in the diamond phase. Our results provide evidences that the recently discovered superconducting transition in boron doped cubic silicon can be explained within a standard phonon-mediated mechanism. The importance of lattice compression and dopant related stretching modes are emphasized. We find that T$_C$ can be increased by one order of magnitude by adopting aluminum doping instead of boron.