Semiclassical Approach to the Physics of Smooth Superlattice Potentials in Graphene

  title={Semiclassical Approach to the Physics of Smooth Superlattice Potentials in Graphene},
  author={Juergen Dietel and Hagen Kleinert},
  journal={Physical Review B},
Due to the chiral nature of the Dirac equation, governing the dynamics of electrons in graphene, overlying of an electrical superlattice (SL) can open new Dirac points on the Fermi surface of the energy spectrum. These lead to novel low-excitation physical phenomena. A typical example for such a system is neutral graphene with a symmetrical unidirectional SL. We show here that in smooth SLs, a semiclassical approximation provides a good mathematical description for particles. Due to the one… 
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