First principles optical spectra of the β-SiC(0 0 1)/Al interface

The optical spectra of the β-SiC(0 0 1)/Al interface has been studied using first principles time-dependent density functional theory. We considered the bare random phase approximation as well as two different exchange-correlation kernels, i.e. the adiabatic-local-density-approximation and the jellium-with-gap kernel of Trevisanutto et al (2013 Phys. Rev. B 87 205143). We investigated the C-terminated interface with Al-C interaction which has quite good bond adhesion between the two materials. The absorption spectra of all methods are dependent on the electric field polarization, showing high anisotropy in these systems. When the electric field is parallel to the interface plane, all methods predict a metallic behavior, while enhanced semiconductor excitonic effects are present when the electric field is perpendicular to the interface plane. Between the considered methods, the jellium-with-gap kernel enhances the excitonic effects of the β-SiC(0 0 1)/Al interface with respect to the other methods.