Nematicity and in-plane anisotropy of superconductivity in β-FeSe detected by 77Se nuclear magnetic resonance

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • S. H. Baek - , Leibniz Institute for Solid State and Materials Research Dresden (Author)
  • D. V. Efremov - , Leibniz Institute for Solid State and Materials Research Dresden (Author)
  • J. M. Ok - , Pohang University of Science and Technology (Author)
  • J. S. Kim - , Pohang University of Science and Technology (Author)
  • Jeroen Van Den Brink - , Chair of Solid State Theory, Leibniz Institute for Solid State and Materials Research Dresden (Author)
  • B. Büchner - , Chair of Experimental Solid State Physics, Leibniz Institute for Solid State and Materials Research Dresden (Author)

Abstract

The recent study of Se77 nuclear magnetic resonance (NMR) in a β-FeSe single crystal proposed that ferro-orbital order breaks the 90 C4 rotational symmetry, driving nematic ordering. Here, we report an NMR study of the impact of small strains generated by gluing on nematic state and spin fluctuations. We observe that the local strains strongly affect the nematic transition, considerably enhancing its onset temperature. On the contrary, no effect on low-energy spin fluctuations was found. Furthermore we investigate the interplay of the nematic phase and superconductivity. Our study demonstrates that the twinned nematic domains respond unequivalently to superconductivity, evidencing the twofold C2 symmetry of superconductivity in this material. The obtained results are well understood in terms of the proposed ferro-orbital order.

Details

Original languageEnglish
Article number180502
JournalPhysical Review B
Volume93
Issue number18
Publication statusPublished - 10 May 2016
Peer-reviewedYes