Theory of optical transitions in graphene nanoribbons

  title={Theory of optical transitions in graphene nanoribbons},
  author={Ken-ichi Sasaki and K. Kato and Yoshinori Tokura and Katsuya Oguri and Tetsuomi Sogawa},
  journal={Physical Review B},
Matrix elements of electron-light interactions for armchair and zigzag graphene nanoribbons are constructed analytically using a tight-binding model. The changes in wavenumber ($\Delta n$) and pseudospin are the necessary elements if we are to understand the optical selection rule. It is shown that an incident light with a specific polarization and energy, induces an indirect transition ($\Delta n=\pm1$), which results in a characteristic peak in absorption spectra. Such a peak provides… 

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