First-principles molecular dynamics study on temperature-dependent dielectric function of bulk 3C and 6H SiC in the energy range 3–8 eV

Abstract

The present work aims at investigating the temperature-dependent dielectric function of cubic (3C) and hexagonal (6H) SiC in the energy range 3–8eV. To compute the temperature effect, the first-principles molecular dynamics (FPMD) method is implemented that can effectively calculate the finite temperature electronic band structure, density of states and dielectric function. In comparison with experimental data, the FPMD approach successfully predicts the dielectric spectra of 3C and 6H SiC over the temperature range from 90K to 538K. The convincing results enable us to predict the dielectric function of SiC at higher temperature.