Electro-optical properties of a strain-induced borocarbonitride monolayer from many-body perturbation theory

Abstract

Exploiting novel graphene-like materials with superior properties is of great interest for nano-optoelectronics. Here, we explore the electro-optical properties of a novel borocarbonitride (C₆BN) monolayer and biaxial strain effects by using many-body perturbation theory calculations (G₀W₀ + Bethe–Salpeter equation). The structure of the C₆BN monolayer is verified to be dynamically stable in a broad tensile strain range, while it is unstable under compressive strains. The direct semiconducting nature of the system is robust to the tensile strain, and the moderate quasi-particle bandgap can decrease linearly with the increased tensile strain. Also, the applied tensile strain on the C₆BN monolayer causes a variation in the optical transitions, red-shifting the optical absorption peaks to the lower photon energies, thus inducing a significant enhancement of the near-infrared light absorption. In addition, the binding energy and real-space distribution for the bright bound exciton are also investigated using tensile strain. Our findings show that the C₆BN monolayer is unique under the tensile strain, making it a potential candidate for nano-optoelectronic devices.