Cohesive energies calculation of Gallium-Arsenide and Aluminium-Arsenide: DFT study

Abstract

A detailed calculation of quantum mechanical first principle theoretical studies of Gallium-Arsenide (GaAs) and Aluminum-Arsenide (AlAs) based on Density Functional Theory (DFT) within the Local Density Approximation (LDA) for the exchange-correlation potential has been performed using Fritz Haber Institute Ab-initio Molecular Simulations (FHI-aims) code. The code has several input parameters in which some of the variables were optimized. The cohesive energies of GaAs and AlAs were calculated within LDA of Perdew Wang of the density functional theory. The results obtained from the computation of the cohesive energies of GaAs and AlAs were 6.94 eV and 8.79 eV respectively which revealed a good agreement in the
exchange correction functional when compared to the experimental values of 6.75 eV and 8.00 eV for GaAs and AlAs respectively. These energies are within reasonable percentage errors of 2.6% and 9.9% respectively. This indicate that GaAs can exhibit high transport property of the electron in the semiconductor which makes it suitable for optoelectronics devices and the AlAs indicate their potentials can be used in high temperature and strong electric fields device applications.