Stripe Antiferromagnetic Spin Fluctuations in SrCo2As2

Journal Article · Tue Jan 01 04:00:00 EST 2013 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.111.157001· OSTI ID:1104811

Jayasekara, W. ^[1]; Lee, Y ^[1]; Pandey, Abishek ^[1]; Tucker, G. S. ^[1]; Sapkota, A ^[1]; Lamsal, Jagat ^[1]; Calder, Stuart A ^[2]; Abernathy, Douglas L ^[2]; Niedziela, Jennifer L ^[2]; Harmon, B N ^[1]; Kreyssig, A. ^[1]; Vaknin, D ^[1]; Johnston, D C ^[1]; Goldman, A. I. ^[1]; McQueeney, R. J. ^[1]

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1. Ames Laboratory and Iowa State University
2. ORNL

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.

• Research Organization: Oak Ridge National Laboratory (ORNL); High Flux Isotope Reactor; Spallation Neutron Source
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1104811
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 15 Vol. 111; ISSN 0031-9007
• Country of Publication: United States
• Language: English