A Comparative Study of Optical Anisotropies of BC3 and B3C Systems by Density Functional Theory

Abstract

The optical properties of (8,0) BC3 and B3C single-wall carbon nanotubes (SWCNTs) are computed using ab initio density functional theory (DFT). The electronic band structure reveals that the Fermi energy of B3C system is reduced compared to BC3. The static dielectric constant in the long wavelength limit for B3C system is 9 times larger than that of BC3 in unpolarized electromagnetic field. Within 10 eV frequency (energy) range, the absorption coefficient of B3C is higher compared to BC3, while, above 10 eV, it is less than that of BC3. In parallel polarization, the peak of the loss function for B3C is shifted to higher frequency (energy) region with significantly six orders of magnitude compared to BC3 system. The analysis of this study indicates that the optical anisotropies can be gained easily in these boron-doped systems by appropriately choosing the direction of the polarization of the electromagnetic field. Besides, the results of the loss functions may throw some light on the nature of collective excitations of these two systems.