title: Nanoscale electronic order in iron pnictides.
abstract: The charge distribution in RFeAsO1-xFx (R=La,Sm) iron pnictides is probed using As nuclear quadrupole resonance. Whereas undoped and optimally doped or overdoped compounds feature a single charge environment, two charge environments are detected in the underdoped region. Spin-lattice relaxation measurements show their coexistence at the nanoscale. Together with the quantitative variations of the spectra with doping, they point to a local electronic order in the iron layers, where low- and high-doping-like regions would coexist. Implications for the interplay of static magnetism and superconductivity are discussed.
authors.affiliation: IFW Dresden, Institute for Solid State Research, P.O. Box 270116, D-01171 Dresden, Germany. g.m.lang@ifw-dresden.de
authors.forename: G
authors.initials: G
authors.lastname: Lang
authors.forename: H-J
authors.initials: HJ
authors.lastname: Grafe
authors.forename: D
authors.initials: D
authors.lastname: Paar
authors.forename: F
authors.initials: F
authors.lastname: Hammerath
authors.forename: K
authors.initials: K
authors.lastname: Manthey
authors.forename: G
authors.initials: G
authors.lastname: Behr
authors.forename: J
authors.initials: J
authors.lastname: Werner
authors.forename: B
authors.initials: B
authors.lastname: Büchner