Superconductivity origin of PdTe and pressure effect: Insights from first-principles investigation

The phonon spectra and electron-phonon interaction properties of hexagonal superconductor PdTe are studied systematically for the first time by density functional perturbation theory (DFPT). We present phonon dispersion with non-negative frequency in the whole Brillouin zone and reveal its three-dimensional character and strong vibrational coupling from both electronic and lattice dynamic viewpoint. First-principles calculation of logarithmically averaged frequency, Debye temperature, electron-phonon coupling constant and transition temperature Tc agree well with experimental values. It is definitely believed superconductivity of PdTe originates from isotropical nonlocal electron-phonon interaction. Moreover, Unlike FeTe, the transition temperature of PdTe decreases with increasing of pressure. (C) 2015 Elsevier Masson SAS. All rights reserved.