Strain-tunable electronic, elastic, and optical properties of CaI2 monolayer: first-principles study

Abstract

ABSTRACT The effects of biaxial strain on the electronic structure and the elastic and optical properties of monolayer CaI2 were studied using first-principles calculations. The two-dimensional (2D) equation of state for monolayer CaI2 as fit in a relative area of 80–120% is more accurate. The band gap can be tuned under strain and reached a maximum at a tensile strain of 4%. Under compressive strains, the absorption spectrum showed a significant red shift at higher strains. The static reflectance and static refractive index decreased in the strain range of −10% to 10%.