Optical spectra of AB- and AA-stacked nanographite ribbons

• Published in: Journal of the Physical Society of Japan 2003-01, Vol.72 (1), p.170-177
• Main Authors: CHIU, C. W, SHYU, F. L, CHANG, C. P, CHEN, R. B, LINE, M. F
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic structure of nanoscale materials : clusters, nanoparticles, nanotubes, and nanocrystals; Exact sciences and technology; Nanocrystals and nanoparticles; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics
• ISSN: 0031-9015; 1347-4073
• DOI: 10.1143/jpsj.72.170

The absorption spectra of the AB- and AA-stacked nanographite ribbons have several prominent peaks. They strongly depend on the edge structure, the ribbon width, the stacking sequence, and the polarization direction. The armchair ribbons quite differ from the zigzag ribbons. The frequency and the number of the absorption peaks are affected by the ribbon width. The AB-stacked systems have lower threshold absorption frequency, more absorption peaks, and weaker spectral intensity, as compared with the AA-stacked systems. The absorption spectra are highly anisotropic. The optical excitations of the parallel polarization (E|||\\hatz) are absent in the AA-stacked systems. Comparison with graphite is discussed.