Flat Bands as a Route to High-Temperature Superconductivity in Graphite

  • Tero T. Heikkilä
  • Grigory E. Volovik
Part of the Springer Series in Materials Science book series (SSMATERIALS, volume 244)


Superconductivity is traditionally viewed as a low-temperature phenomenon. Within the BCS theory this is understood to result from the fact that the pairing of electrons takes place only close to the usually two-dimensional Fermi surface residing at a finite chemical potential. Because of this, the critical temperature is exponentially suppressed compared to the microscopic energy scales. On the other hand, pairing electrons around a dispersionless (flat) energy band leads to very strong superconductivity, with a mean-field critical temperature linearly proportional to the microscopic coupling constant. The prize to be paid is that flat bands can probably be generated only on surfaces and interfaces, where high-temperature superconductivity would show up. The flat-band character and the low dimensionality also mean that despite the high critical temperature such a superconducting state would be more vulnerable to strong fluctuations than ordinary superconductors. Here we discuss the topological and non-topological flat bands discussed in different systems, and show that graphite is a good candidate for showing high-temperature flat-band interface superconductivity.


Fermi Surface Topological Charge Topological Insulator Dirac Point Flat Band 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We acknowledge Pablo Esquinazi, Ville Kauppila and Timo Hyart for discussions. This work was supported by the Academy of Finland through its Center of Excellence program, and by the European Research Council (Grant No. 240362-Heattronics).


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Department of Physics and Nanoscience CenterUniversity of JyväskyläJyvaskylaFinland
  2. 2.Low Temperature Laboratory, Department of Applied PhysicsAalto UniversityAaltoFinland
  3. 3.L. D. Landau Institute for Theoretical PhysicsMoscowRussia

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