Electron-phonon coupling of α-Ga boron -: art. no. 214107

The electronic properties, lattice dynamics, and electron-phonon coupling of boron with alpha-Ga structure are studied as a function of pressure by ab initio calculations. It is found that alpha-Ga boron is dynamically stable at high pressure. Electron-phonon calculations suggest that alpha-Ga boron is superconducting with strong anisotropy. Analysis of the phonon linewidths shows that the in-plane sigma-bonding states couple strongly with the y-z in-plane vibrations, contributing mainly to the electron-phonon coupling. The theoretical results suggest that the alpha-Ga structure might be a good candidate for the high-pressure metallic phase of boron.