Dirac cone

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Dirac cones are features that occur in some electronic band structures that describe unusual electron transport properties of materials like graphene and topological insulators.[1] In these materials, at energies near the Fermi level, the valence band and conduction band take the shape of the upper and lower halves of a conical surface, meeting at what are called Dirac points. Dirac points only occur as a feature of two-dimensional materials, a linear dispersion in three dimensions is called a Weyl point.[2] As a result of the cones, electrical conduction can be described by the movement of charge carriers which are massless fermions, a situation which is handled theoretically by the relativistic Dirac equation.[3] The massless fermions lead to various quantum Hall effects and ultra high carrier mobility.[4]

References[edit]

  1. ^ "Superconductors: Dirac cones come in pairs". AIM research highlights. 29 Aug 2011. Retrieved 2 Mar 2018. 
  2. ^ Ling Lu, Liang Fu, John D. Joannopoulos and Marin Soljacˇic (17 Mar 2013). "Weyl points and line nodes in gyroid photonic crystals" (PDF). Nature Photonics. Retrieved 2 Mar 2018. 
  3. ^ K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, M. I. Katsnelson, I. V. Grigorieva, S. V. Dubonos & A. A. Firsov (10 Nov 2005). "Two-dimensional gas of massless Dirac fermions in graphene". Nature. Retrieved 2 Mar 2018. 
  4. ^ "Two-dimensional Dirac materials: Structure, properties, and rarity". Phys.org. Retrieved May 25, 2016.