Anisotropic Neutron Spin Resonance in Superconducting BaFe${}_{1.9}$Ni${}_{0.1}$As${}_2$

Abstract

We use polarized inelastic neutron scattering to show that the neutron spin resonance below $T_c$ in superconducting BaFe${}_{1.9}$Ni${}_{0.1}$As${}_2$ ($T_c=20$ K) is purely magnetic in origin. Our analysis further reveals that the resonance peak near 7~meV only occurs for the planar response. This challenges the common perception that the spin resonance in the pnictides is an isotropic triplet excited state of the singlet Cooper pairs, as our results imply that only the $S_{001}=\pm 1$ components of the triplet are involved.

References in corpus (10)

• Magnetic order in BaFe2As2, the parent compound of the FeAs based superconductors in a new structural family
• Lattice and magnetic instabilities in CaFe2As2: A single crystal neutron diffraction study
• Theory of magnetic excitations in iron-based layered superconductors
• Spin resonance in the d-wave superconductor CeCoIn5
• Two-dimensional resonant magnetic excitation in BaFe1.84Co0.16As2
• Spin and Lattice Structure of Single Crystal SrFe2As2
• Neutron scattering as a probe of the Fe-pnicitide superconducting gap
• Three-dimensional Resonance in superconducting BaFe${}_{1.9}$Ni${}_{0.1}$As${}_2$
• Neutron Scattering Resonance and the Fe-pnictide Superconducting Gap
• Resonance in the electron-doped high-Tc superconductor Pr0.88LaCe0.12CuO(4-delta)

Cited by in corpus (12)

• High-temperature superconductivity in iron-based materials
• Spin reorientation in Na-doped BaFe${}_2$As${}_2$ studied by neutron diffraction
• Magnetic anisotropy in hole-doped superconducting Ba 0.67K 0.33Fe 2As2 probed by polarized inelastic neutron scattering
• Anisotropic neutron spin resonance in underdoped superconducting NaFe1-xCoxAs
• Polarized neutron scattering studies of magnetic excitations in electron-overdoped superconducting BaFe${}_{1.85}$Ni${}_{0.15}$As${}_2$
• Anisotropy of incommensurate magnetic excitations in slightly overdoped Ba${}_{0.5}$K${}_{0.5}$Fe${}_2$As${}_2$ probed by polarized inelastic neutron scattering experiments
• Eliashberg Analysis of Optical Spectra Reveals Strong Coupling of Charge Carriers to Spin Fluctuations in Superconducting Iron Pnictides
• Spin anisotropy due to spin-orbit coupling in optimally hole-doped Ba${}_{0.67}$K${}_{0.33}$Fe${}_2$As${}_2$
• Spin resonance peak in Fe-based superconductors with unequal gaps
• Vortex dynamics as a function of field orientation in BaFe1.9Ni0.1As2
• Spin-orbit coupling in Fe-based superconductors
• Impurity-induced smearing of the spin resonance peak in Fe-based superconductors