Evidence of local disorder in the overdoped regime of Ba(Fe(1-x)Co(x))(2)As(2)

TitleEvidence of local disorder in the overdoped regime of Ba(Fe(1-x)Co(x))(2)As(2)
Publication TypeJournal Article
Year of Publication2011
AuthorsPark K, Louca D, Llobet A, Yan JQ
Journal TitlePhysical Review B
Volume84
Pages024512
Date Published07
ISBN Number1098-0121
Accession NumberWOS:000292648200005
Abstract

The appearance of superconductivity in the antiferromagnet of BaFe(2)As(2) with Co doping coincides with a phase transition from an orthorhombic to a tetragonal structure where coexistence of the two is observed near the phase boundary. Overdoping brings suppression of T(C) near x = 0.12 that is not accompanied by a transition back to the orthorhombic phase. Using pulsed neutron powder diffraction, the relation of superconductivity to the atomic structure in the overdoped regime has been investigated. The suppression of superconductivity is accompanied by a structural local distortion around Co. The distortion, described as a breathing mode with alternating two or four Fe ions displaced toward Co in the ab plane, sets in above T(C) and remains in place below.

DOI10.1103/PhysRevB.84.024512