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Local density of states at zigzag edge of carbon nanotubes and graphene

K. Sasaki·K. Sato·J. Jiang·R. Saito·S. Onari·Y. Tanaka
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Abstract

The electron-phonon matrix element for edge states of carbon nanotubes and graphene at zigzag edges is calculated for obtaining renormalized energy dispersion of the edge states. Self-energy correction by electron-phonon interaction contributes to the energy dispersion of edge states whose energy bandwidth is similar to phonon energy. Since the energy-uncertainty of the edge state is larger than temperature, we conclude that the single-particle picture of the edge state in not appropriate when the electron-phonon interaction is taken into account. The longitudinal acoustic phonon mode contributes to the matrix element through the on-site deformation potential because the wavefunction of the edge state has an amplitude only on one of the two sublattices. The on-site deformation potentials for the longitudinal and in-plane tangential optical phonon modes are enhanced at the boundary. The results of local density of states are compared with the recent experimental data of scanning tunneling spectroscopy.

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K. Sasaki, K. Sato, J. Jiang, R. Saito, S. Onari, Y. Tanaka. 2007-03-14. Local density of states at zigzag edge of carbon nanotubes and graphene. https://doi.org/10.1103/physrevb.75.235430

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