Analysis of the Electronic Band Structure in Two-Dimensional Materials Using Tight-Binding Models and Numerical Simulation

Abstract

The Electronic Band Structures of selected Two-Dimensional (2D) materials such as Graphene, Hexagonal Boron Nitride (h-BN), Molybdenum Disulfide (MoS₂) and Tungsten Disulfide (WS₂) are studied by Tight-Binding (TB) model and numerical simulation methods. The Tight-Binding approximation and Bloch theory were used to formulate a theoretical model, which was used to compute the electronic energy bands for the directions of high symmetry in the Brillouin zone. The numerical results showed that the electronic properties of materials studied were significantly different. Graphene had gapless band structure with Dirac cones while the MoS₂ and WS₂ showed finite direct band gap as a semiconductor material. Contrastingly, the band gap of hBN was large, which was consistent with its insulating properties. The connection between hopping parameters and electronic bandwidth was also investigated and the obtained results indicate that higher values of electronic coupling led to wider energy bands. The results demonstrated the power of the Tight-Binding method in the study and prediction of the electronic properties of 2D materials and its potential applications in the fields of nanoelectronics and optoelectronics.