DIELECTRIC RESPONSE AND OPTICAL PROPERTY OF AL

Abstract

The dielectric response and the optical property of Al are studied through first-principles pseudopotential calculations. The frequency and wave vector dependent dielectric function is calculated for various wave vectors along the [100] direction within the random phase approximation. In the limit q-->0, we find two prominent peaks at 0.5 and 1.5 eV in the conductivity and attribute these peaks to the parallel bands near the Fermi level. Considering the exchange-correlation and core polarization effects, we find good agreement of the calculated plasma frequencies with experiments. The anisotropy of the plasmon dispersion between the [100] and [111] directions is also investigated by calculating the electron energy-loss function.