Electronic Structure of GaAs and AlAs using a Hamiltonian Tight-Binding sp3s∗

We calculate the electronic states in volume for GaAs and AlAs in Zinc-Blenda structure using the Tight-Binding (TB) method. The TB Hamiltonian was constructed using a base of s, p and s∗ orbitals. Thes∗ orbitals represent excited states with equal symmetry as the s orbitals. Carrying out the numeri...

Full description

Bibliographic Details
Main Authors:	Rasero Causil, Diego Alejandro, Portacio, Alfonso A., Suescun , Daniel
Format:	Online
Language:	spa
Published:	Universidad Pedagógica y Tecnológica de Colombia 2021
Subjects:	Tight-Binding, relaciones de dispersión, densidad de estados. Tight-Binding, dispersion relations, density of states.
Online Access:	https://revistas.uptc.edu.co/index.php/ciencia_en_desarrollo/article/view/12612

Description
Summary:	We calculate the electronic states in volume for GaAs and AlAs in Zinc-Blenda structure using the Tight-Binding (TB) method. The TB Hamiltonian was constructed using a base of s, p and s∗ orbitals. Thes∗ orbitals represent excited states with equal symmetry as the s orbitals. Carrying out the numericaldiagonalization of the Hamiltonian, the dispersion relationships were determined for some directions ofhigh symmetry of the first Brillouin zone (FBZ), obtaining a direct gap of 1.54 eV for GaAs and an indirectgap of 2.26 eV for AlAs. The total (DOS) and partial state densities indicate the presence of s orbitals inthe lower part of the valence band (BV), p orbitals in the upper part of the BV and in the lower part of theconduction band (BC), and s∗ orbitals on top of BC. Our results agree quite well with other experimentaland theoretical reports.