Vibrational and dielectric properties of AlN: A first-principles study

Abstract

The vibrational and dielectric properties of zinc-blende aluminum nitride (B3-AlN) were investigated within the framework of density functional perturbation theory. The phonon frequencies at the Brillouin zone center, the static dielectric constant, and the electronic dielectric constant were reported. The results of our studies were analyzed and discussed with respect to the available experimental and theoretical data. We found that the generalized gradient approximation potential resulted in more accurate phonon frequencies than those obtained using the local density approximation potential. The contributions to the static dielectric tensor due to purely electronic screening and infrared-active phonon modes were analyzed. The phonon, dielectric, refractive index, extinction coefficient and infrared reflectance spectra of B3-AlN were reported, and their values suggest that B3-AlN has good transmission properties in the spectral range above 1000cm−1 and below 400cm−1.