2018年3月27日
Neutron Spin Resonance in the 112-Type Iron-Based Superconductor
Physical Review Letters
- 巻
- 120
- 号
- 13
- 開始ページ
- 137001
- 終了ページ
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1103/PhysRevLett.120.137001
- 出版者・発行元
- American Physical Society
We use inelastic neutron scattering to study the low-energy spin excitations of the 112-type iron pnictide Ca0.82La0.18Fe0.96Ni0.04As2 with bulk superconductivity below Tc=22 K. A two-dimensional spin resonance mode is found around E=11 meV, where the resonance energy is almost temperature independent and linearly scales with Tc along with other iron-based superconductors. Polarized neutron analysis reveals the resonance is nearly isotropic in spin space without any L modulations. Because of the unique monoclinic structure with additional zigzag arsenic chains, the As 4p orbitals contribute to a three-dimensional hole pocket around the Γ point and an extra electron pocket at the X point. Our results suggest that the energy and momentum distribution of the spin resonance does not directly respond to the kz dependence of the fermiology, and the spin resonance intrinsically is a spin-1 mode from singlet-triplet excitations of the Cooper pairs in the case of weak spin-orbital coupling.
- ID情報
-
- DOI : 10.1103/PhysRevLett.120.137001
- ISSN : 1079-7114
- ISSN : 0031-9007
- SCOPUS ID : 85044731270