Computational Investigation of Electronic and Optical Properties of Si, Ge and Si1-xGex Alloys Using the FP-LMTO Method Augmented by a Plane-Wave Basis

Abstract

An investigation into the structural, electronic and optical properties of Si, Ge, and Si1-xGex for different compositions was conducted using first-principles calculations based on density functional theory (DFT). The total energies were calculated within the full -potential linear muffin-tin orbital (FP-LMTO) method augmented by a plane-wave basis (PLW), implemented in Lmtar code. The effects of the approximations to the exchange-correlation energy were treated by the local density approximation (LDA). From our simulation results, it is found that the theoretical ground-state parameters, the band structure, the density of states (DOS), the chemical bonding and the optical properties agree well with the experi- ment and other theoretical calculations. The accuracies found from the present calculations allow us to describe the proper- ties of the electronic as well as the optoelectronic devices based on the Si1-xGex alloy.