Novel Graphene-like Co₂VAl (111): Case Study on Magnetoelectronic and Optical Properties by First-Principles Calculations

Abstract

The electronic, magnetic, and optical properties of the Co 2 VAl (111) graphene-like (GL) monolayer as well as the (101) and (011) terminations have been calculated on the basis of the density functional theory (DFT) and FP-LAPW+lo method. The GL (111) Co 2 VAl has been grown in the (111)-crystallographic direction, leading to various and interesting physical properties compared to those of their considered directions. The films grown in the (101) and (011) directions have shown metallic behavior with low spin-polarization at the Fermi level, while the GL case has shown a perfect half-metallic behavior with an integer amount of magnetic moment (1.00 μ B ) and 0.5 eV spin-flip gap. Thus, it can be a good candidate for spintronic applications. Although all of these thin films behave similarly in the ultraviolet region, the GL case appears to be different in the infrared and visible regions. The main plasmonic energies occur in the 12–13.8 eV energy range in the parallel ( xx ) and perpendicular ( zz ) directions. Our results show that the incident light cannot propagate in the visible region for all the considered monolayers.