Počet záznamů: 1

Doping dependence of spin fluctuations and electron correlations in iron pnictides

  1. 1.
    0352183 - FZU-D 2011 RIV US eng J - Článek v odborném periodiku
    Ikeda, H. - Arita, R. - Kuneš, Jan
    Doping dependence of spin fluctuations and electron correlations in iron pnictides.
    Physical Review. B. Roč. 82, č. 2 (2010), 024508/1-024508/6 ISSN 1098-0121
    Výzkumný záměr: CEZ:AV0Z10100521
    Klíčová slova: iron pnicitdes * dynamic spin susceptibility * fluctuation-exchange approximation
    Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
    Impakt faktor: 3.772, rok: 2010
    http://prb.aps.org/abstract/PRB/v82/i2/e024508

    Doping dependence of the spin fluctuations and the electron correlations in the effective five-band Hubbard model for iron pnictides is investigated using the fluctuation-exchange approximation. For a moderate hole doping, we find a dominant low-energy spin excitation at Q=(Π,0) which becomes critical at low temperature. The low-energy spin excitations in the heavily hole-doped region are characterized by weak Q dependence. The electron doping leads to an appearance of a pseudogap in spin-excitation spectrum. Correspondingly, the NMR-1/T1 relaxation rate is strongly enhanced on the hole-doped side and suppressed on the electron-doped side of the phase diagram. This behavior can be to large extent understood by systematic changes of the Fermi-surface topology.
    Trvalý link: http://hdl.handle.net/11104/0191757