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JETP Letters

, Volume 84, Issue 12, pp 650–655 | Cite as

Electronic theory for itinerant in-plane magnetic fluctuations in Na x CoO2

  • M. M. Korshunov
  • I. Eremin
  • A. Shorikov
  • V. I. Anisimov
Condensed Matter

Abstract

Starting from the ab initio band structure for Na x CoO2, we derive the single-electron energies and the effective tight-binding description for the t 2g bands using a projection procedure. We find that, due to the presence of the next-nearest-neighbor hoppings, a local minimum in the electronic dispersion close to the Γ point of the first Brillouin zone forms. Therefore, in addition to a large Fermi surface, an electron pocket close to the Γ point emerges at high doping concentrations. The latter yields a new scattering channel resulting in the peak structure of the itinerant magnetic susceptibility at low momenta. This indicates an itinerant in-plane ferromagnetic state above a certain critical concentration x m , which is in agreement with neutron scattering data. Below x m , the magnetic susceptibility shows a tendency towards antiferromagnetic fluctuations. We estimate the value of 0.56 < x m < 0.68 within the rigid band model and within the Hubbard model with infinite on-site Coulomb repulsion consistent with the experimental phase diagram.

PACS numbers

31.15.Ar 71.10.-w 74.70.-b 75.40.Cx 

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References

  1. 1.
    K. Takada et al., Nature 422, 53 (2003).CrossRefADSGoogle Scholar
  2. 2.
    I. Terasaki, Y. Sasago, and K. Uchinokura, Phys. Rev. B 56, 12 685(R) (1997).Google Scholar
  3. 3.
    Y. Wang et al., Nature 423, 425 (2003).CrossRefADSGoogle Scholar
  4. 4.
    M. L. Foo et al., Phys. Rev. Lett. 92, 247001 (2004).Google Scholar
  5. 5.
    B. C. Sales et al., Phys. Rev. B 70, 174419 (2004).Google Scholar
  6. 6.
    D. J. Singh, Phys. Rev. B 61, 13397 (2000).Google Scholar
  7. 7.
    K.-W. Lee, J. Kuneš, and W. E. Pickett, Phys. Rev. B 70, 045104 (2004).Google Scholar
  8. 8.
    M. Z. Hasan et al., Phys. Rev. Lett. 92, 246402 (2004).Google Scholar
  9. 9.
    H.-B. Yang et al., Phys. Rev. Lett. 92, 246403 (2004).Google Scholar
  10. 10.
    H.-B. Yang et al., Phys. Rev. Lett. 95, 146401 (2005).Google Scholar
  11. 11.
    D. Qian et al., Phys. Rev. Lett. 96, 216405 (2006).Google Scholar
  12. 12.
    D. J. Singh, Phys. Rev. B 68, 020503(R) (2003).Google Scholar
  13. 13.
    A. T. Boothroyd et al., Phys. Rev. Lett. 92, 197201 (2004).Google Scholar
  14. 14.
    S. P. Bayrakci et al., Phys. Rev. Lett. 94, 157205 (2005).Google Scholar
  15. 15.
    L. M. Helme et al., Phys. Rev. Lett. 94, 157206 (2005).Google Scholar
  16. 16.
    W. Kohn and L. J. Sham, Phys. Rev. A 140, 1133 (1965).CrossRefMathSciNetADSGoogle Scholar
  17. 17.
    O. K. Andersen and O. Jepsen, Phys. Rev. Lett. 53, 2571 (1984).CrossRefADSGoogle Scholar
  18. 18.
    J. D. Jorgensen et al., Phys. Rev. B 68, 214517 (2003).Google Scholar
  19. 19.
    N. Marzari and D. Vanderbilt, Phys. Rev. B 56, 12 847 (1997).Google Scholar
  20. 20.
    V. I. Anisimov et al., Phys. Rev. B 71, 125119 (2005).Google Scholar
  21. 21.
    M. D. Johannes et al., Europhys. Lett. 68, 433 (2004).CrossRefADSGoogle Scholar
  22. 22.
    K. Kuroki et al., Phys. Rev. B 73, 184503 (2006).Google Scholar
  23. 23.
    M. Renner and W. Brenig, cond-mat/0310244 (unpublished).Google Scholar
  24. 24.
    S. Borisenko, private communication.Google Scholar
  25. 25.
    M. D. Johannes et al., Phys. Rev. Lett. 93, 097005 (2004).Google Scholar
  26. 26.
    S. Zhou et al., Phys. Rev. Lett. 94, 206401 (2005).Google Scholar
  27. 27.
    M. Indergand et al., Phys. Rev. B 71, 214414 (2005).Google Scholar
  28. 28.
    J. C. Hubbard, Proc. R. Soc. London, Ser. A 277, 237 (1964).ADSCrossRefGoogle Scholar
  29. 29.
    R. O. Zaitsev, Sov. Phys. JETP 41, 100 (1975).ADSGoogle Scholar
  30. 30.
    Yu. Izumov and B. M. Letfullov, J. Phys.: Condens. Matter 3, 5373 (1991).CrossRefADSGoogle Scholar
  31. 31.
    S. G. Ovchinnikov and V. V. Val’kov, Hubbard Operators in the Theory of Strongly Correlated Electrons (Imperial College Press, London, 2004).zbMATHGoogle Scholar

Copyright information

© Pleiades Publishing, Inc. 2006

Authors and Affiliations

  • M. M. Korshunov
    • 1
    • 2
  • I. Eremin
    • 2
    • 3
  • A. Shorikov
    • 4
  • V. I. Anisimov
    • 4
  1. 1.Kirensky Institute of Physics, Siberian DivisionRussian Academy of SciencesKrasnoyarskRussia
  2. 2.Max-Planck-Institut für Physik komplexer SystemsDresdenGermany
  3. 3.Institut für Mathematische Physik and Theoretische PhysikTU BraunschweigBraunschweigGermany
  4. 4.Institute of Metal Physics, Ural DivisionRussian Academy of SciencesYekaterinburg, GSP-170Russia

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