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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
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Stripe antiferromagnetic spin fluctuations in SrCo2As2
W Jayasekara1, Y Lee, Abhishek Pandey
1Ames Laboratory, Ames, Iowa 50011, USA and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
Physical Review Letters
|October 29, 2013
Summary
Antiferromagnetic spin fluctuations were observed in SrCo2As2, suggesting stripe antiferromagnetism is common in iron and cobalt arsenides. This finding expands the search for unconventional superconductivity to cobalt-based materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid State Physics
Background:
- Antiferromagnetic (AFM) spin fluctuations are crucial in understanding magnetism in materials.
- AFe2As2 compounds exhibit spin-density wave AFM driven by Fermi surface nesting.
- SrCo2As2 is a cobalt-based arsenide with potential magnetic instabilities.
Purpose of the Study:
- To investigate the magnetic properties of paramagnetic SrCo2As2.
- To determine the nature and characteristics of spin fluctuations in SrCo2As2.
- To explore the implications for magnetism and superconductivity in cobalt-based arsenides.
Main Methods:
- Inelastic neutron scattering measurements were performed on SrCo2As2 at 5 K.
- Analysis of scattering data to identify wave vectors and energy scales of spin fluctuations.
- Comparison with band-structure calculations and known properties of related compounds.
Main Results:
- Antiferromagnetic spin fluctuations were detected in SrCo2As2, peaked at Q(AFM)=(1/2,1/2,1).
- These fluctuations exhibit a large energy scale, characteristic of stripe spin fluctuations.
- The findings suggest similarities to spin-density wave mechanisms in AFe2As2 compounds.
Conclusions:
- Stripe antiferromagnetism appears to be a general characteristic of both iron and cobalt-based arsenides.
- The study indicates that cobalt-based compounds should be included in the search for unconventional superconductivity.
- Fermi surface nesting and band structure play a significant role in the magnetic ground state of these materials.
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