Effect of electric field on two-dimensional honeycomb structures from group (III–V)

The last few decades have seen an immense development of interest in two-dimensional materials, which can be integrated in either mono-, bi-, tri- or tetra-layer form. The tuning of physical properties of 2D materials is a prevalent challenge since they disclose enormous opportunities for electronic and opto-electronic devices. The functionality of two dimensional (2D) materials can be enhanced through several external factors such as strain, defects, doping, electric field, stacking, and mechanical stress, etc. Recently, the two-dimensional III-V (III = B, Al, Ga, In, Tl and V = N, P, As, Sb, and Bi) monolayers have been theoretically discovered. The present research has been designed to study the variations in their properties under a small range of external electric field. Previous studies have been highlighted which suggested that electric field can be an effective approach to improve the physical properties of 2D materials. In this paper, the influence of an external electric field, in the range of −0.3 VA−1 to 0.3 VA−1, on the structural, electronic and optical properties of III-V monolayers has been investigated using the first-principles calculations in the context of density functional theory (DFT). The results suggest that monolayers retain their geometrical properties. However, the electric field enhances the strength of covalent bonds. The results also disclose that the bandgap of these monolayers can be widely tuned with the help of electric field. As the electric field is raised, few of the monolayers exhibit transition from semiconducting to conducting behavior. Moreover, the optical absorption is also observed to modify with electric field. The amount of absorption and the energy at which electronic transitions occur vary uniformly with electric field. The transparency of few monolayers in visible region alongwith maximum absorption in UV region ensures their potential for Visible-blind UV detectors, flat panel displays and window layers in solar cells. The bandgap-type transition promise their application in low-power electronic devices and widely tunable bandgap shows their potential for various opto-electronic devices. The findings of this paper focus on the contribution of III-V monolayers to the development of more efficient electronic and opto-electronic devices.