Local magnetic inhomogeneities in Ba(Fe1-xNix)(2)As-2 as seen via As-75 NMR

TitleLocal magnetic inhomogeneities in Ba(Fe1-xNix)(2)As-2 as seen via As-75 NMR
Publication TypeJournal Article
Year of Publication2010
AuthorsDioguardi AP, apRoberts-Warren N, Shockley AC, Bud'ko SL, Ni N, Canfield PC, Curro NJ
Journal TitlePhysical Review B
Volume82
Pages140411
Date Published10/26
ISBN Number1098-0121
Accession NumberISI:000283487900003
Keywordsbafe2as2, metals, relaxation, superconductivity
Abstract

We report As-75 NMR measurements in BaFe2As2 doped with Ni. Like Co, Ni doping suppresses the antiferromagnetic and structural phase transitions and gives rise to superconductivity for sufficiently large Ni doping. The spin-lattice relaxation rate diverges at T-N with a critical exponent consistent with three-dimensional ordering of local moments. In the ordered state the spectra quickly broaden inhomogeneously with doping. We extract the average size of the ordered moment as a function of doping and show that a model in which the order remains commensurate but with local amplitude variations in the vicinity of the dopant fully explains our observations.

URL<Go to ISI>://000283487900003http://prb.aps.org/pdf/PRB/v82/i14/e140411
DOI10.1103/Physrevb.82.140411
Alternate JournalPhys Rev B