Evidence of unconventional low-frequency dynamics in the normal phase of Ba(Fe1-xRhx)(2)As-2 iron-based superconductors

TitleEvidence of unconventional low-frequency dynamics in the normal phase of Ba(Fe1-xRhx)(2)As-2 iron-based superconductors
Publication TypeJournal Article
Year of Publication2013
AuthorsBossoni L, Carretta P, Halperin WP, Oh S, Reyes A, Kuhns P, Canfield PC
Journal TitlePhysical Review B
Volume88
Pages100503
Date Published09
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberWOS:000324631200002
KeywordsMOTION, nmr, order, spin-echo decay, susceptibility, transition, transverse relaxation rate, vortex lattice, yba2cu3o7-delta
Abstract

This work presents As-75 NMR spin-echo decay rate (1/T-2) measurements in Ba(Fe1-xRhx)(2)As-2 superconductors, for 0.041 <= x <= 0.094. It is shown that 1/T-2 increases upon cooling, in the normal phase, suggesting the onset of an unconventional very low-frequency activated dynamic. The correlation times of the fluctuations and their energy barriers are derived. The motion is favored at large Rh content, while it is hindered by the application of a magnetic field perpendicular to the FeAs layers. The same dynamic is observed in the spin-lattice relaxation rate, in a quantitatively consistent manner. These results are discussed in the light of nematic fluctuations involving domain wall motion. The analogies with the behavior observed in the cuprates are also outlined.

URL<Go to ISI>://WOS:000324631200002
DOI10.1103/PhysRevB.88.100503