Campus Units
Physics and Astronomy, Ames Laboratory
Document Type
Article
Publication Version
Published Version
Publication Date
7-1-2012
Journal or Book Title
Physical Review B
Volume
86
Issue
2
First Page
024505
DOI
10.1103/PhysRevB.86.024505
Abstract
The magnetic excitations in the paramagnetic-tetragonal phase of underdoped Ba(Fe0.953Co0.047)(2)As-2, as measured by inelastic neutron scattering, can be well described by a phenomenological model with purely diffusive spin dynamics. At low energies, the spectrum around the magnetic ordering vector QAFM consists of a single peak with elliptical shape in momentum space. At high energies, this inelastic peak is split into two peaks across the direction perpendicular to QAFM. We use our fittings to argue that such a splitting is not due to incommensurability or propagating spin-wave excitations, but is rather a consequence of the anisotropies in the Landau damping and in the magnetic correlation length, both of which are allowed by the tetragonal symmetry of the system. We also measure the magnetic spectrum deep inside the magnetically ordered phase, and find that it is remarkably similar to the spectrum of the paramagnetic phase, revealing the strongly overdamped character of the magnetic excitations.
Copyright Owner
American Physical Society
Copyright Date
2012
Language
en
File Format
application/pdf
Recommended Citation
Tucker, G. S.; Fernandes, R. M.; Li, H.-F.; Thampy, V.; Ni, N.; Abernathy, D. L.; Bud’ko, Sergey L.; Canfield, Paul C.; Vaknin, David; Schmalian, J.; and McQueeney, Robert J., "Magnetic excitations in underdoped Ba(Fe1-xCox)(2)As-2 with x=0.047" (2012). Physics and Astronomy Publications. 647.
https://lib.dr.iastate.edu/physastro_pubs/647
Comments
This article is published as Tucker, Gregory S., R. M. Fernandes, H-F. Li, Vivek Thampy, Ni Ni, Douglas L. Abernathy, Serguei L. Bud'ko, P. C. Canfield, D. Vaknin, J. Schmalian, and R. J. McQueeney. "Magnetic excitations in underdoped Ba (Fe 1− x Co x) 2 As 2 with x= 0.047." Physical Review B 86, no. 2 (2012): 024505. DOI: 10.1103/PhysRevB.86.024505. Posted with permission.