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The Deformation Effect on the Electronic Structure of the Graphite Nanoribbon Arrays

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 نشر من قبل Bi-Ru Wu
 تاريخ النشر 2008
  مجال البحث فيزياء
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We have performed a first-principles study on the deformation effect of the electronic structures of graphite nanoribbon arrays with zigzag edges on both sides, and the edge atoms are terminated with hydrogen atoms. A uniaxial strain is considered to have deformation effect on the graphite nanoribbons. We found that the antiferromagnetic arrangement of the spin polarizing edges of graphite nanoribbon is still more favorable than that with the ferromagnetic arrangement under deformation. We also learned that a tensile strain increases the magnetization of the graphite ribbon while a compressive strain decreases it. A positive pressure derivative of the band gap of antiferromagnetic state is observed for the graphite nanoribbon under uniaxial strains. The strain changes the shape of band structure and the band gap; in here, the edge atoms play a crucial role. The deformations are also found to influence the contribution of the edge atoms to the bands near the Fermi level. The deformation effect for the graphite nanoribbon under transverse electric field is also studied.

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