title: Coexistence of cluster spin glass and superconductivity in Ba(Fe(1-x)Co(x))2As2 for 0.060≤x≤0.071.
abstract: We present 75As nuclear magnetic resonance data from measurements of a series of Ba(Fe(1-x)Co(x))2As2 crystals with 0.00≤x≤0.075 that reveals the coexistence of frozen antiferromagnetic domains and superconductivity for 0.060≤x≤0.071. Although bulk probes reveal no long range antiferromagnetic order beyond x=0.06, we find that the local spin dynamics reveal no qualitative change across this transition. The characteristic domain sizes vary by more than an order of magnitude, reaching a maximum variation at x=0.06. This inhomogeneous glassy dynamics may be an intrinsic response to the competition between superconductivity and antiferromagnetism in this system.
authors.affiliation: Department of Physics, University of California, Davis, California 95616, USA.
authors.forename: A P
authors.initials: AP
authors.lastname: Dioguardi
authors.forename: J
authors.initials: J
authors.lastname: Crocker
authors.forename: A C
authors.initials: AC
authors.lastname: Shockley
authors.forename: C H
authors.initials: CH
authors.lastname: Lin
authors.forename: K R
authors.initials: KR
authors.lastname: Shirer
authors.forename: D M
authors.initials: DM
authors.lastname: Nisson
authors.forename: M M
authors.initials: MM
authors.lastname: Lawson
authors.forename: N
authors.initials: N
authors.lastname: apRoberts-Warren
authors.forename: P C
authors.initials: PC
authors.lastname: Canfield
authors.forename: S L
authors.initials: SL
authors.lastname: Bud'ko
authors.forename: S
authors.initials: S
authors.lastname: Ran
authors.forename: N J
authors.initials: NJ
authors.lastname: Curro