Absorption-spectral features of single-walled carbon nanotubes

• Main Authors: Zhao, Yang, Wang, Xiujun, Ma, Chi Chiu, Chen, Guan Hua
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Materials::Nanostructured materials
• Online Access: https://hdl.handle.net/10356/99691; http://hdl.handle.net/10220/6777
• Institution: Nanyang Technological University

We present a visual, intuitive connection between optical absorption line shapes and the underlying carbon nanotube structures. Within the tight-binding model, the absorption spectra can be linked directly to plots of energy contours and transition dipoles of a graphene sheet. Via two additional approaches, spectral features are shown only slightly altered by electronic correlations and σ–π oorbital rehybridization. Despite dependence of electronic structures on chiral angles, it is proved that, if the tube diameter D is greater than the C–C bond length a, the absorption spectra are determined by D to the lowest order in a/D.