Abstract
Inelastic neutron scattering measurements of paramagnetic SrCo2As2 at T = 5 K reveal antifer-
romagnetic (AFM) spin fluctuations that are peaked at a wavevector of QAFM = (1/2, 1/2, 1) and
possess a large energy scale. These stripe spin fluctuations are similar to those found in AFe2As2
compounds, where spin-density wave AFM is driven by Fermi surface nesting between electron and
hole pockets separated by QAFM. SrCo2As2 has a more complex Fermi surface and band structure
calculations indicate a potential instability towards either a ferromagnetic or stripe AFM ground
state. The results suggest that stripe AFM magnetism is a general feature of both iron and cobalt-
based arsenides and the search for spin fluctuation-induced unconventional superconductivity should
be expanded to include cobalt-based compounds.
