Magnetic excitations in underdoped Ba(Fe1-xCox)2As2 with x=0.047

Abstract

The magnetic excitations in the paramagnetic-tetragonal phase of underdoped Ba(Fe0.953Co0.047)2As2, as measured by inelastic neutron scattering, can be well described by a phenomenological model with purely diffusive spin dynamics. At low energies, the spectrum around the magnetic ordering vector Q_AFM consists of a single peak with elliptical shape in momentum space. At high energies, this inelastic peak is split into two peaks across the direction perpendicular to Q_AFM. We use our fittings to argue that such a splitting is not due to incommensurability or propagating spin-wave excitations, but is rather a consequence of the anisotropies in the Landau damping and in the magnetic correlation length, both of which are allowed by the tetragonal symmetry of the system. We also measure the magnetic spectrum deep inside the magnetically-ordered phase, and find that it is remarkably similar to the spectrum of the paramagnetic phase, revealing the strongly overdamped character of the magnetic excitations.

12 pages, 7 figures

References in corpus (10)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Theory of Electron Nematic Order in LaOFeAs
• Effects of Co substitution on thermodynamic and transport properties and anisotropic $H_{c2}$ in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ single crystals
• Ising and Spin orders in Iron-based Superconductors
• Itinerant magnetic excitations in antiferromagnetic CaFe2As2
• Symmetry of spin excitation spectra in the tetragonal paramagnetic and superconducting phases of 122-ferropnictides
• Incommensurate spin-density wave order in electron-doped BaFe2As2 superconductors
• Itinerant Spin Excitations in SrFe2As2 Measured by Inelastic Neutron Scattering
• Dispersion of the superconducting spin resonance in underdoped and antiferromagnetic Ba(Fe1-xCox)2As2

Cited by in corpus (12)

• Strong $(\pi ,0)$ spin fluctuations in $\beta$-FeSe observed by neutron spectroscopy
• Effective One-Dimensional Coupling in the Highly-Frustrated Square-Lattice Itinerant Magnet CaCo${}_{2-y}$As${}_2$
• Neutron-scattering measurements of the spin excitations in LaFeAsO and Ba(Fe${}_{0.953}$Co${}_{0.047}$)${}_2$As${}_2$: Evidence for a sharp enhancement of spin fluctuations by nematic order
• Spin-orbital interplay and topology in the nematic phase of iron pnictides
• Magnonlike dispersion of spin resonance in Ni-doped BaFe${}_2$As${}_2$
• NMR study of nematic spin fluctuations in a detwinned single crystal of underdoped Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Crossover from spin-waves to diffusive spin excitations in underdoped Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Distinct itinerant spin-density waves and local-moment antiferromagnetism in an intermetallic ErPd${}_2$Si${}_2$ single crystal
• Anisotropic inplane spin correlation in the parent and Co-doped BaFe2As2: a neutron scattering study
• Magnetoelastic coupling and charge correlation lengths in a twin domain of Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ ($x=0.047$): A high-resolution X-ray diffraction study
• Spin fluctuations in the 112-type iron-based superconductor Ca${}_{0.82}$La${}_{0.18}$Fe${}_{0.96}$Ni${}_{0.04}$As${}_2$
• Ground and Applied-Field-Driven Magnetic States of Antiferromagnets