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Fermi surface and mass enhancement in KFe$_2$As$_2$ from de Haas-van Alphen effect measurements

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 نشر من قبل Taichi Terashima
 تاريخ النشر 2010
  مجال البحث فيزياء
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We report on a band structure calculation and de Haas-van Alphen measurements of KFe$_2$As$_2$. Three cylindrical Fermi surfaces are found. Effective masses of electrons range from 6 to 18$m_e$, $m_e$ being the free electron mass. Remarkable discrepancies between the calculated and observed Fermi surface areas and the large mass enhancement ($gtrsim 3$) highlight the importance of electronic correlations in determining the electronic structures of iron pnicitide superconductors.



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