This title appears in the Scientific Report : 2016 

Strong interplay between stripe spin fluctuations, nematicity and superconductivity in FeSe
Wang, Qisi
Shen, Yao / Pan, Bingying / Hao, Yiqing / Ma, Mingwei / Zhou, Fang / Steffens, P. / Schmalzl, K. / Forrest, T. R. / Abdel-Hafiez, M. / Chen, Xiaojia / Chareev, D. A. / Vasiliev, A. N. / Bourges, P. / Sidis, Y. / Cao, Huibo / Zhao, Jun (Corresponding author)
Streumethoden; JCNS-2
Streumethoden; PGI-4
Nature materials, 15 (2016) S. 159–163
Basingstoke Nature Publishing Group 2016
Journal Article
Jülich Centre for Neutron Research (JCNS)
Materials and Processes for Energy and Transport Technologies
Quantum Condensed Matter: Magnetism, Superconductivity
Controlling Collective States
Controlling Collective States
Please use the identifier: in citations.
In iron-based superconductors the interactions driving the nematic order (that breaks four-fold rotational symmetry in the iron plane) may also mediate the Cooper pairing1. The experimental determination of these interactions, which are believed to depend on the orbital or the spin degrees of freedom1, 2, 3, 4, is challenging because nematic order occurs at, or slightly above, the ordering temperature of a stripe magnetic phase1, 5. Here, we study FeSe (ref. 6)—which exhibits a nematic (orthorhombic) phase transition at Ts = 90 K without antiferromagnetic ordering—by neutron scattering, finding substantial stripe spin fluctuations coupled with the nematicity that are enhanced abruptly on cooling through Ts. A sharp spin resonance develops in the superconducting state, whose energy (~4 meV) is consistent with an electron–boson coupling mode revealed by scanning tunnelling spectroscopy7. The magnetic spectral weight in FeSe is found to be comparable to that of the iron arsenides8, 9. Our results support recent theoretical proposals that both nematicity and superconductivity are driven by spin fluctuations