Non-nesting spin density wave antiferromagnetism in FeAs: first principles calculations
- ORNL
- Naval Research Laboratory, Washington, D.C.
The antiferromagnetic state of FeAs is unusual in several aspects, and seems to be rather complicated. The Fe spins form an incommensurate magnetic spiral pattern with a relatively short wavelength, about 15 A. To model this, we have performed first principles calculations and found that the nearest-neighbor AFM ordering is energetically favorable, with the lowest-energy pattern reproducing the experimentally found nearest neighbor correlations. Other antiferromagnetic orderings are also very stable, even though higher in energy; the Fermi-surface geometry thus plays little role. We calculate the bare Lindhard susceptibility in the AFM state and find that the observed spin-density wave ordering vector \textbf{Q} $$\simeq(0,0,0.4)$$ is \textit{not} that given by this calculation. Thus the observed pattern must be due to a subtler mechanism, such as frustration created by the competing ground states.
- Research Organization:
- Oak Ridge National Laboratory (ORNL)
- Sponsoring Organization:
- SC USDOE - Office of Science (SC)
- DOE Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1024260
- Journal Information:
- Physical Review B, Journal Name: Physical Review B Journal Issue: 18 Vol. 83; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
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