Direct observation of dark excitons in micelle-wrapped single-wall carbon nanotubes.
We have performed electroabsorption spectroscopy on micelle-wrapped single-wall carbon nanotubes. In semiconducting nanotubes, many oscillating structures composed of the increase and decrease of absorption are observed in the spectra in the region of the first and second absorption bands, E11 and E22. The spectral shape is reproduced mainly by the second-derivative curve of the absorption spectrum, which indicates the presence of nearly degenerate bright and dark excitonic states.
Kishida
Hideo
H
Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 Japan. kishida@nuap.nagoya-u.ac.jp
Nagasawa
Yoshiaki
Y
Imamura
Sadanobu
S
Nakamura
Arao
A