Structural and Electronic Properties of Gallium Phosphate Semiconductor in Wurtzite Rock-Salt and Zinc-Blende

Abstract

First principle method was used to study the structural and electronic properties of Gallium Phosphate in Wurtzite, zinc blende and rock salt using the molecular dynamics density functional theory implemented on the Quantum Espresso software. For this work the choice of the pseudo-potential is the GGA, scf calculation was used for zinc blende and rock salt to test the convergence of kinetic energy cut-off, lattice parameter, number of k-point with respect to 1mRy energy and 0.5kbar pressure. The same was repeated in wurtzite but vc-relax was used, all the plots obtained for the three structure converges towards the set threshold, the plot of band structure and density of state reveals that rock salt is a metal due to absence of band gap while other are semi-conductors with an indirect band gap, a plot of energy versus enthalpy shows that there’s a transition from zinc blende to rock salt with about 18.73% decrease in volume from zinc blende to rock salt and this occur at a pressure of 29.07GPa, it is noteworthy that Gallium Phosphate was found to be more stable in zinc blende.