Eur. Phys. J. B 43, 439-444 (2005)
https://doi.org/10.1140/epjb/e2005-00076-8

First-principles study of the optical properties of pure α-Al₂O₃ and La aluminates

Department of Physics, Ferdowsi University of Mashad (Electroceramic and Material Laboratory), Mashhad, Iran

Corresponding author: ^a smahosseini@yahoo.com

Received: 1 September 2004
Revised: 8 November 2004
Published online: 30 March 2005

Abstract

The optical properties of high k-gate α-Al₂O₃ and the effect of doping La have been studied by first principles using the density functional theory. The calculations were performed using the full potential–linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation (GGA). The calculated optical properties and EEL spectrum yield a static refractive index of 1.64 and a plasmon energy of 21.6 eV for pure α-Al₂O₃. Substitution of La for Al increases the static refractive index to 1.73, but decreases the plasmon energy to 17.8 eV for the Al_1.5La_0.5O₃ molecule.