%0 Journal Article
%A Song, Yu
%A Man, Haoran
%A Zhang, Rui
%A Lu, Xingye
%A Zhang, Chenglin
%A Wang, Meng
%A Tan, Guotai
%A Regnault, L.-P.
%A Su, Yixi
%A Kang, Jian
%A Fernandes, Rafael M.
%A Dai, Pengcheng
%T Spin anisotropy due to spin-orbit coupling in optimally hole-doped Ba $_{0.67}$ K $_{0.33}$ Fe $_{2}$ As $_{2}$
%J Physical review / B
%V 94
%N 21
%@ 2469-9950
%C Woodbury, NY
%I Inst.
%M FZJ-2017-01820
%P 214516
%D 2016
%X We use polarized inelastic neutron scattering to study the temperature and energy dependence of spin space anisotropies in the optimally-hole-doped iron pnictide Ba0.67K0.33Fe2As2 (Tc=38 K). In the superconducting state, while the high-energy part of the magnetic spectrum is nearly isotropic, the low-energy part displays a pronounced anisotropy, manifested by a c-axis polarized resonance. We also observe that the spin anisotropy in superconducting Ba0.67K0.33Fe2As2 extends to higher energies compared with electron-doped BaFe2−xTMxAs2 (TM=Co, Ni) and isovalent-doped BaFe2As1.4P0.6, suggesting a connection between Tc and the energy scale of the spin anisotropy. In the normal state, the low-energy spin anisotropy for hole- and electron-doped iron pnictides near optimal superconductivity onset at temperatures similar to the temperatures at which the elastoresistance deviates from Curie–Weiss behavior, pointing to a possible connection between the two phenomena. Our results highlight the relevance of the spin-orbit coupling to the superconductivity of the iron pnictides.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000390906100008
%R 10.1103/PhysRevB.94.214516
%U https://juser.fz-juelich.de/record/827712