%0 Journal Article
%T Orbital character and electron correlation effects on two- and three-dimensional Fermi surfaces in KFe2As2 revealed by angle-resolved photoemission spectroscopy
%A Teppei Yoshida
%A Atsushi Fujimori
%A Ming Yi
%A Sung-Kwan Mo
%A Donghui Lu
%A Zahid Hussain
%J Frontiers in Physics
%D 2014
%I Frontiers Media
%R 10.3389/fphy.2014.00017
%X We have investigated orbital character and electron correlation effects on Fermi surfaces in the hole-overdoped iron pnictide superconductor KFe2As2, which shows a low Tc of ~4 K, by angle-resolved photoemission spectroscopy. From the polarization-dependence of the ARPES spectra, we have determined the orbital character of each Fermi surface. Electron mass renormalization of each band is quantitatively consistent with de Haas-van Alphen results. The outer ¦Â and middle ¦Æ Fermi surfaces show large renormalization factor of m*/mb ~6¨C7, while the inner ¦Á Fermi surface has a smaller factor m*/mb ~2. Middle hole Fermi surface ¦Æ has strong three-dimensionality compared to other Fermi surfaces, indicating the d3z2¨Cr2 orbital character, which may be related to the ¡°octet-line nodes¡± recently observed by laser ARPES. The observed orbital-dependent mass renormalization would give constraints on the pairing mechanism with line nodes of this system.
%K iron pnictide superconductor
%K angle-resolved photoemission spectroscopy
%K electron correlation
%U http://www.frontiersin.org/Journal/10.3389/fphy.2014.00017/abstract