Journal of Superconductivity and Novel Magnetism

, Volume 22, Issue 6, pp 603–607

Iron-Based Layered Compounds: The Effect of Negative Interband Coupling

Original Paper

Abstract

The experimental data relative to new superconductor LaFeAsO1−xFx can be analyzed in the framework of the two-band Eliashberg theory. With reasonable assumptions on input parameters of the theory such as electron–phonons and electron-antiferromagnetic spin density fluctuations spectral functions and the Coulomb pseudopotential, it is possible to calculate mean physical quantities such as critical temperature, superconductive gaps, superconductive differential conductance, and so on. In this model also the effect of disorder and magnetic impurities on the critical temperature is examined. The key ingredient is the negative interband coupling that can remarkably increase the critical temperature. This effect stems from the presence of an electron–phonon coupling constant smaller than the sum of the Coulomb pseudopotential and electron-antiferromagnetic spin density fluctuations coupling constant in the interband channel. The resulting superconductive state is an example of extended s-wave pairing with a sign reversal of the order parameter between different Fermi surface sheets.

Keywords

Multiband Eliashberg theory Fe-based pnictides 

PACS

74.70.Dd 74.20.Fg 74.20.Mn 

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References

  1. 1.
    Kamihara, Y., Watanabe, T., Hirano, M., Hosono, H.: J. Am. Chem. Soc. 130, 3296–3297 (2008) CrossRefGoogle Scholar
  2. 2.
    Wen, H.-H., Mu, G., Fang, L., Yang, H., Zhu, X.: Europhys. Lett. 82, 17009 (2008) CrossRefADSGoogle Scholar
  3. 3.
    Wang, C., Li, L., Chi, S., Zhu, Z., Ren, Z., Li, Y., Wang, Y., Lin, X., Luo, Y., Xu, X., Cao, G., Xu, Z.: Europhys. Lett. 83, 67006 (2008) CrossRefADSGoogle Scholar
  4. 4.
    Eliashberg, G.M.: Sov. Phys. JETP 3, 696 (1963) Google Scholar
  5. 5.
    Scalapino, D.J.: In: Parks, R.D. (ed.) Superconductivity, p. 449. Marcel Dekker, New York (1969) Google Scholar
  6. 6.
    Carbotte, J.P.: Rev. Mod. Phys. 62, 1028 (1990) CrossRefADSGoogle Scholar
  7. 7.
    Allen, P.B., Mitrovich, B.: Theory of superconducting T c. In: Ehrenreich, H., Seitz, F., Turnbull, D. (eds.) Solid State Physics, vol. 37. Academic Press, New York (1982) Google Scholar
  8. 8.
    Marsiglio, F., Carbotte, J.P.: In: Bennemann, K.H., Ketterson, J.B. (eds.) The Physics of Conventional and Unconventional Superconductors. Springer, Berlin (2003) Google Scholar
  9. 9.
    Marsiglio, F.: J. Low Temp. Phys. 87, 659 (1992) CrossRefADSGoogle Scholar
  10. 10.
    Boeri, L., Dolgov, O.V., Golubov, A.A.: Phys. Rev. Lett. 101, 026403 (2008) CrossRefADSGoogle Scholar
  11. 11.
    Mazin, I.I., Singh, D.J., Johannes, M.D., Du, M.H.: Phys. Rev. Lett. 101, 057003 (2008) CrossRefADSGoogle Scholar
  12. 12.
    Parker, D., Dolgov, O.V., Korshunov, M.M., Golubov, A.A., Mazin, I.I.: Phys. Rev. B 78, 134524 (2008) CrossRefADSGoogle Scholar
  13. 13.
    Dolgov, O.V., Mazin, I.I., Parker, D., Golubov, A.A.: Phys. Rev. B 79, 060502(R) (2009) CrossRefADSGoogle Scholar
  14. 14.
    Kulic, M.L., Drechsler, S.L., Dolgov, O.V.: Europhys. Lett. 85, 47008 (2009) CrossRefADSGoogle Scholar
  15. 15.
    Ummarino, G.A.: J. Superconduct. Novel Magn. 20(7–8), 639–642 (2007) CrossRefGoogle Scholar
  16. 16.
    Shulga, S.V., Drechsler, S.L., Fuchs, G., Muller, K.H., Winzer, K., Heinecke, M., Krug, K.: Phys. Rev. Lett. 80, 1730 (1998) CrossRefADSGoogle Scholar
  17. 17.
    Adrian, S.D., Wolf, S.A., Dolgov, O.V., Shulga, S., Kresin, V.Z.: Phys. Rev. B 56, 7878 (1997) CrossRefADSGoogle Scholar
  18. 18.
    Konsin, P., Kristoffel, N., Sorkin, B.: J. Phys.: Condens. Matter 10, 6533–6539 (1998) CrossRefADSGoogle Scholar
  19. 19.
    Kugel, K.I., Rakhmanov, A.L., Sboychakov, A.O., Poccia, N., Bianconi, A.: Model Phys. Rev. B 78, 165124 (2008) CrossRefADSGoogle Scholar
  20. 20.
    Nicol, E.J., Carbotte, J.P.: Phys. Rev. B 71, 054501 (2005) CrossRefADSGoogle Scholar
  21. 21.
    Ummarino, G.A., Gonnelli, R.S., Massidda, S., Bianconi, A.: Physica C 407, 121 (2004) CrossRefADSGoogle Scholar
  22. 22.
    Konsin, P., Sorkin, B.: Supercond. Sci. Technol. 17, 1472–1476 (2004) CrossRefADSGoogle Scholar
  23. 23.
    Kuchinskii, E.Z., Sadovskii, M.V.: (unpublished). arXiv:0901.0164 cond-mat.supr-con
  24. 24.
    Bose, S.K., Dolgov, O.V., Kortus, J., Jepsen, O., Andersen, O.K.: Phys. Rev. B 67, 214518 (2003) CrossRefADSGoogle Scholar
  25. 25.
    Gonnelli, R.S., Daghero, D., Tortello, M., Ummarino, G.A., Stepanov, V.A., Kremer, R.K., Kim, J.S., Zhigadlo, N.D., Karpinski, J.: (unpublished). arXiv:0902.3441 cond-mat.supr-con
  26. 26.
    Sadovskii, M.V.: Phys.-Usp. 51(12), 1201–1227 (2008) CrossRefADSGoogle Scholar
  27. 27.
    Fratini, R.C.M., Poccia, N., Ricci, A., Puri, A., Ren, Z.-A., Dong, X.-L., Yang, J., Lu, W., Zhao, Z.-X., Barba, L., Bianconi, A.: Supercond. Sci. Technol. 22, 014004 (2009) CrossRefADSGoogle Scholar
  28. 28.
    Golubov, A.A., Mazin, I.I.: Phys. Rev. B 55, 15146 (1997) CrossRefADSGoogle Scholar
  29. 29.
    Vidberg, H.J., Serene, J.W.: J. Low Temp. Phys. 29, 179 (1977) CrossRefADSGoogle Scholar
  30. 30.
    Leavens, C.R., Ritchie, D.S.: Solid State Commun. 53, 137 (1985) CrossRefADSGoogle Scholar
  31. 31.
    Mazin, I.I., Schmalian, J.: (unpublished). arXiv:0901.4790 cond-mat.supr-con

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.CNISM-Dipartimento di FisicaPolitecnico di TorinoTorinoItaly

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