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Pseudogap Value in the Energy Spectrum of LaOFeAs: Fixed Spin Moment Treatment

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 نشر من قبل Dr. M. A. Korotin
 تاريخ النشر 2008
  مجال البحث فيزياء
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The experimental data available up to date in literature corresponding to the paramagnetic - spin density wave transition in nonsuperconducting LaOFeAs are discussed. In particular, we pay attention that upon spin density wave transition there is a relative decrease of the density of states on the Fermi level and a pseudogap formation. The values of these quantities are not properly described in frames of the density functional theory. The agreement of them with experimental estimations becomes more accurate with the use of fixed spin moment procedure when iron spin moment is set to experimental value. Strong electron correlations which are not included into the present calculation scheme may lead both to the decrease of spin moment and renormalization of energy spectrum in the vicinity of the Fermi level for correct description of discussed characteristics.

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