Theoretical investigation of the electronic and optical properties of gallium-doped hexagonal boron nitride through Monte Carlo and ab initio calculations

Abstract

We modify a hBN monolayer through substitutional gallium atoms in boron and nitrogen sites. The configurations were created by means of the simulated annealing algorithm, a Monte Carlo calculation based process. As a result, it was found that monoatomic bonds appear during the process in almost all studied structures. The electronic and optical properties were calculated based on first-principles calculations through the SIESTA method, using density functional theory. The results showed that, due to the monoatomic bonds arisen with the present method, localized states appear close to the bandgap. In addition, from the optical absorption and the conductivity analyses we found the presence of states in the visible region of the spectrum, whose intensity and distribution depend on the doping type, which is an important fact if we are interested in the usage of such compounds in the fabrication of optoelectronic nanodevices. With respect to the materials conductivity, it is also shown that it can be controlled by the doping processes.