Electronic structure and optical properties of 2D hexagonal Boron Arsenide

We examine the electronic structure of two-dimensional hexagonal boron arsenide using k.p theory, method of invariants, and density functional theory. The fundamental band gap occuring at the K point is 0.76 eV, however, this transition is not allowed in the dipole approximation. The conduction band at the Γ point is highly sensitive to strain or electric fields that renders transition into a metallic state possible. We investigate the optical absorption of boron arsenide and the possibilities of tuning by means of strain or electric field.