Anisotropic and quasipropagating spin excitations in superconducting Ba(Fe0.926Co0.074)(2)As-2

TitleAnisotropic and quasipropagating spin excitations in superconducting Ba(Fe0.926Co0.074)(2)As-2
Publication TypeJournal Article
Year of Publication2010
AuthorsLi HF, Broholm C, Vaknin D, Fernandes RM, Abernathy DL, Stone MB, Pratt DK, Tian W, Qiu Y, Ni N, Diallo SO, Zarestky JL, Bud'ko SL, Canfield PC, McQueeney RJ
Journal TitlePhysical Review B
Volume82
Pages140503
Date Published10/12
ISBN Number1098-0121
Accession NumberISI:000282809100004
Keywordsstate
Abstract

Inelastic neutron scattering from superconducting (SC) Ba (Fe0.926Co0.074)(2)As-2 reveals anisotropic and quasi-two-dimensional (2D) magnetic excitations close to Q(AFM)=(1/21/2) - the 2D antiferromagnetic (AFM) wave vector of the parent BaFe2As2 compound. The correlation length anisotropy of these low-energy fluctuations is consistent with spin nematic correlations in the J(1)-J(2) model with J(1)/J(2)similar to 1. The spin resonance at similar to 8.3 meV in the SC state displays the same anisotropy. The anisotropic fluctuations experimentally evolve into two distinct maxima only along the direction transverse to Q(AFM) above similar to 80 meV indicating unusual quasipropagating excitations.

URL<Go to ISI>://000282809100004http://prb.aps.org/pdf/PRB/v82/i14/e140503
DOI10.1103/Physrevb.82.140503
Alternate JournalPhys Rev B