title: Strong electron correlations in the normal state of the iron-based FeSe0.42Te0.58 superconductor observed by angle-resolved photoemission spectroscopy.
abstract: We investigate the normal state of the "11" iron-based superconductor FeSe0.42Te0.58 by angle-resolved photoemission. Our data reveal a highly renormalized quasiparticle dispersion characteristic of a strongly correlated metal. We find sheet dependent effective carrier masses between approximately 3 and 16m{e} corresponding to a mass enhancement over band structure values of m{*}/m{band} approximately 6-20. This is nearly an order of magnitude higher than the renormalization reported previously for iron-arsenide superconductors of the "1111" and "122" families but fully consistent with the bulk specific heat.
authors.affiliation: School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife KY16 9SS, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Tamai
authors.forename: A Y
authors.initials: AY
authors.lastname: Ganin
authors.forename: E
authors.initials: E
authors.lastname: Rozbicki
authors.forename: J
authors.initials: J
authors.lastname: Bacsa
authors.forename: W
authors.initials: W
authors.lastname: Meevasana
authors.forename: P D C
authors.initials: PD
authors.lastname: King
authors.forename: M
authors.initials: M
authors.lastname: Caffio
authors.forename: R
authors.initials: R
authors.lastname: Schaub
authors.forename: S
authors.initials: S
authors.lastname: Margadonna
authors.forename: K
authors.initials: K
authors.lastname: Prassides
authors.forename: M J
authors.initials: MJ
authors.lastname: Rosseinsky
authors.forename: F
authors.initials: F
authors.lastname: Baumberger