Publication Type
Journal
Journal Name
Physical Review Letters
Publication Date
Page Number
217202
Volume
112
Issue
21
Abstract
We use inelastic neutron scattering to study spin waves in the antiferromagnetic ordered phase of iron pnictide NaFeAs throughout the Brillouin zone. Comparing with the well-studied AFe2As2 (A = Ca,Sr,Ba) family, spin waves in NaFeAs have considerably lower zone boundary energies and more isotropic effective in-plane magnetic exchange couplings. These results are consistent with calculations from a combined density functional theory (DFT) and dynamical mean field theory (DMFT), and provide strong evidence that pnictogen height controls the strength of electron-electron correlations, and consequently the effective bandwidth of magnetic excitations.
