First-principles study of the electronic and optical properties of Be atoms adsorbed stanene

Abstract

Two-dimensional stanene is limited in its application in nanoscale optoelectronic devices due to its zero-bandgap. Based on first-principles calculations of density functional theory, the effects of adsorption of Be atoms with different coverages and torsional deformation on the structure, electricity, and optics of stanene are systematically investigated. The adsorption of Be atoms makes stanene have an adjustable bandgap, the surface state is successfully transformed from a zero-bandgap quasi-metal to a semiconductor with a maximum bandgap of 0.260 eV, the change in Be atom coverage causes a blueshift of the absorption and reflection peaks. Torsional deformation can effectively adjust the bandgap of stanene, which varies from 0.278 eV to 0.110 eV. Torsion enhances the maximum absorption peak of light. Stanene is expected to be a candidate material for designing new nanoelectronic devices.