Unimpeded tunneling in graphene nanoribbons.

نویسندگان

  • O Roslyak
  • A Iurov
  • Godfrey Gumbs
  • Danhong Huang
چکیده

We studied the Klein paradox in zigzag (ZNR) and anti-zigzag (AZNR) graphene nanoribbons. Due to the fact that ZNR (the number of lattice sites across the nanoribbon = N is even) and AZNR (N is odd) configurations are indistinguishable when treated by the Dirac equation, we supplemented the model with a pseudo-parity operator whose eigenvalues correctly depend on the sublattice wavefunctions for the number of carbon atoms across the ribbon, in agreement with the tight-binding model. We have shown that the Klein tunneling in zigzag nanoribbons is related to conservation of the pseudo-parity rather than pseudo-spin as in infinite graphene. The perfect transmission in the case of head-on incidence is replaced by perfect transmission at the center of the ribbon and the chirality is interpreted as the projection of the pseudo-parity on momentum at different corners of the Brillouin zone.

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عنوان ژورنال:
  • Journal of physics. Condensed matter : an Institute of Physics journal

دوره 22 16  شماره 

صفحات  -

تاریخ انتشار 2010