Electronic properties of monolayer and bilayer arsenene under in-plain biaxial strains

Using first-principles density functional theory, we have investigated the mechanical and electronic properties of monolayer and bilayer arsenenes under in-plain biaxial strains. It is interesting to find that under large enough tensile strains, the monolayer arsenene transfers from buckled honeycomb structure to planar honeycomb phase while the interlayer distance D of bilayer arsenene maintains at about 1.371 Å. Both monolayer and bilayer arsenenes possess indirect band gaps and their electronic properties can be tuned via in-plane biaxial strains. The variations of the band gap energy are diverse with respect to the compressive and tensile biaxial strains. Under compressive strains, the band gap of both monolayer and bilayer arsenenes initially increases, and then rapidly decreases. In addition, the monolayer arsenene exhibits an indirect-to-direct band gap transition when the compressive strains reach to −10%. However, under tensile strains, the band gap of monolayer arsenene monotonously decreases with the strains, while the band gap of bilayer arsenene reduces quickly to zero under small tensile strains. Our present results will be conductive to design strain-based arsenene materials for applications in nanoelectronic and optoelectronic devices.