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Title: Localized states of a semi-infinite zigzag graphene sheet with impurity lines

Abstract

The localized states of a semi-infinite zigzag graphene sheet are studied using a tight-binding model that allows for the inclusion of either one or two lines of impurities. These impurity lines of atoms are placed in rows labeled as n (n=1, 2, 3, …), where n=1 is the free edge. The localized defect modes associated with these impurities are studied analytically and numerically within a tridiagonal matrix formalism. For one impurity line, the modes are analyzed according to the position of that line on the sheet, whereas the modes for two impurities are studied also according to their separation and their positions relative to the edge. When an impurity line is located at the edge (n=1), it is found that the edge states are modified. When the impurities are positioned away from an edge (n>1), additional localized modes are found to occur that may be relatively flat in their dispersion.

Authors:
 [1];  [2];  [3];  [4]
  1. Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, Campus do Pici, 60455-760 Fortaleza, Ceara (Brazil)
  2. Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada and Physics Department, Faculty of Science, Ain Shams University, Abbsai, Cairo (Egypt)
  3. Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)
  4. Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada and Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, Campus do Pici, 60455-760 Fortaleza, Ceara (Brazil)
Publication Date:
OSTI Identifier:
22306171
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 1; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; DEFECTS; DISPERSIONS; GRAPHENE; IMPURITIES; INCLUSIONS; NANOSTRUCTURES

Citation Formats

Cunha, A. M. C., E-mail: amagno@fisica.ufc.br, Ahmed, Maher Z., Cottam, M. G., E-mail: cottam@uwo.ca, and Filho, R. N. Costa, E-mail: rai@fisica.ufc.br. Localized states of a semi-infinite zigzag graphene sheet with impurity lines. United States: N. p., 2014. Web. doi:10.1063/1.4886599.
Cunha, A. M. C., E-mail: amagno@fisica.ufc.br, Ahmed, Maher Z., Cottam, M. G., E-mail: cottam@uwo.ca, & Filho, R. N. Costa, E-mail: rai@fisica.ufc.br. Localized states of a semi-infinite zigzag graphene sheet with impurity lines. United States. doi:10.1063/1.4886599.
Cunha, A. M. C., E-mail: amagno@fisica.ufc.br, Ahmed, Maher Z., Cottam, M. G., E-mail: cottam@uwo.ca, and Filho, R. N. Costa, E-mail: rai@fisica.ufc.br. Mon . "Localized states of a semi-infinite zigzag graphene sheet with impurity lines". United States. doi:10.1063/1.4886599.
@article{osti_22306171,
title = {Localized states of a semi-infinite zigzag graphene sheet with impurity lines},
author = {Cunha, A. M. C., E-mail: amagno@fisica.ufc.br and Ahmed, Maher Z. and Cottam, M. G., E-mail: cottam@uwo.ca and Filho, R. N. Costa, E-mail: rai@fisica.ufc.br},
abstractNote = {The localized states of a semi-infinite zigzag graphene sheet are studied using a tight-binding model that allows for the inclusion of either one or two lines of impurities. These impurity lines of atoms are placed in rows labeled as n (n=1, 2, 3, …), where n=1 is the free edge. The localized defect modes associated with these impurities are studied analytically and numerically within a tridiagonal matrix formalism. For one impurity line, the modes are analyzed according to the position of that line on the sheet, whereas the modes for two impurities are studied also according to their separation and their positions relative to the edge. When an impurity line is located at the edge (n=1), it is found that the edge states are modified. When the impurities are positioned away from an edge (n>1), additional localized modes are found to occur that may be relatively flat in their dispersion.},
doi = {10.1063/1.4886599},
journal = {Journal of Applied Physics},
number = 1,
volume = 116,
place = {United States},
year = {Mon Jul 07 00:00:00 EDT 2014},
month = {Mon Jul 07 00:00:00 EDT 2014}
}
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