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Journal of Superconductivity and Novel Magnetism

, Volume 26, Issue 9, pp 2887–2890 | Cite as

Flat Band in Topological Matter

Possible Route to Room-Temperature Superconductivity
  • G. E. Volovik
Original Paper

Abstract

Topological media are systems whose properties are protected by topology, and thus are robust to deformations of the system. In topological insulators and superconductors, the bulk-surface and bulk-vortex correspondence gives rise to the gapless Weyl, Dirac, or Majorana fermions on the surface of the system and inside vortex cores. In gapless topological media, the bulk-surface and bulk-vortex correspondence produce topologically protected gapless fermions without dispersion—the flat band. Fermion zero modes forming the flat band are localized on the surface of topological media with protected nodal lines and in the vortex core in systems with topologically protected Fermi points (Weyl points). Flat band has an extremely singular density of states, and this property may give rise in particular to surface superconductivity, which in principle could exist even at room temperature.

Keywords

Weyl point Flat band Fermi arc Surface superconductivity 

Notes

Acknowledgements

This work is supported in part by the Academy of Finland and its COE program.

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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.O.V. Lounasmaa LaboratoryAalto UniversityAaltoFinland
  2. 2.L.D. Landau Institute for Theoretical PhysicsMoscowRussia

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