Electronic states of metallic and semiconducting carbon nanotubes with bond and site disorder
نویسنده
چکیده
Disorder effects on the density of states in carbon nanotubes are analyzed by a tight binding model with Gaussian bond or site disorder. Metallic armchair and semiconducting zigzag nanotubes are investigated. In the strong disorder limit, the conduction and valence band states merge, and a finite density of states appears at the Fermi energy in both of metallic and semiconducting carbon nanotubes. The bond disorder gives rise to a huge density of states at the Fermi energy differently from that of the site disorder case. Consequences for experiments are discussed. PACS numbers: 72.80.Rj, 72.15.Eb, 73.61.Wp, 73.23.Ps E-mail address: [email protected]; URL: http://www.etl.go.jp/ ̃harigaya/ Corresponding address
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