Electronic properties and the phonon band structure of PbTe

Abstract

Electronic properties of PbTe in its Rock-Salt (B1) phase have been investigated using density functional theory (DFT) as well as the Phonon Band Structure of PbTe using density functional perturbation theory (DFPT). The lattice parameter, bulk modulus and pressure derivative are calculated as 6.608 Å, 36.00 GPa and 3.39 respectively; The density of states (DOS) has a maximum peak of 3.2 states/eV at −3.00 eV, the spherical charge distributions between the Pb+2 and Te−2 ions depict that the system is an ionic compound; From the band structure, a direct band gap of 0.7968 eV was obtained which agreed well with other calculations. We observed a large splitting value of 2.16 THZ between the longitudinal optic (LO) and the transverse optic (TO) phonon branches along the Γ-point. The vibrational density of states (VDOS) has a maximum peak of 0.185 states/eV at 1.53 THZ. The values obtained for electronic properties and the phonon band structure PbTe are essentially important for PbTe energy applications such as thermoelectric, solar cells, biological imaging electroluminescent, infrared photodetectors and optoelectronic devices.