title: Electronic dispersion anomalies in iron pnictide superconductors.
abstract: Recently, experimental studies of the spin excitation spectrum revealed a strong temperature dependence in the normal state and a resonance feature in the superconducting state of several Fe-based superconductors. Based on these findings, we develop a model of electrons interacting with a temperature dependent magnetic excitation spectrum and apply it to angle resolved photoemission in Ba(1-x)K(x)Fe(2)As(2). We reproduce in quantitative agreement with experiment a renormalization of the quasiparticle dispersion both in the normal and the superconducting state, and the dependence of the quasiparticle linewidth on binding energy. We estimate the strength of the coupling between electronic and spin excitations. Our findings support a dominantly magnetic pairing mechanism.
authors.affiliation: Institut für Theoretische Festkörperphysik, Karlsruhe Institute of Technology, Karlsruhe, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Heimes
authors.forename: Roland
authors.initials: R
authors.lastname: Grein
authors.forename: Matthias
authors.initials: M
authors.lastname: Eschrig