TITLE:
Determination of Band Structure of Gallium-Arsenide and Aluminium-Arsenide Using Density Functional Theory
AUTHORS:
J. A. Owolabi, M. Y. Onimisi, S. G. Abdu, G. O. Olowomofe
KEYWORDS:
FHI-Aims, Local Density Approximation, Band Structure, Energy Band Gap, Density of State, Gallium Arsenide, and Aluminium Arsenide
JOURNAL NAME:
Computational Chemistry,
Vol.4 No.3,
July
5,
2016
ABSTRACT: This research paper is on Density Functional Theory (DFT) within Local Density Approximation.
The calculation was performed using Fritz Haber Institute Ab-initio Molecular Simulations (FHIAIMS)
code based on numerical atomic-centered orbital basis sets. The electronic band structure,
total density of state (DOS) and band gap energy were calculated for Gallium-Arsenide and
Aluminium-Arsenide in diamond structures. The result of minimum total energy and computational
time obtained from the experimental lattice constant 5.63 A for both Gallium Arsenide
and Aluminium Arsenide is -114,915.7903 eV and 64.989 s, respectively. The electronic band
structure analysis shows that Aluminium-Arsenide is an indirect band gap semiconductor while
Gallium-Arsenide is a direct band gap semiconductor. The energy gap results obtained for GaAs
is 0.37 eV and AlAs is 1.42 eV. The band gap in GaAs observed is very small when compared to
AlAs. This indicates that GaAs can exhibit high transport property of the electron in the semiconductor
which makes it suitable for optoelectronics devices while the wider band gap of AlAs
indicates their potentials can be used in high temperature and strong electric fields device applications.
The results reveal a good agreement within reasonable acceptable errors when compared
with the theoretical and experimental values obtained in the work of Federico and Yin
wang [1] [2].