Two-dimensional magnetic interactions in LaFeAsO

M. Ramazanoglu; 1; 2 J. Lamsal; 2 G. S. Tucker; 2 J. -Q. Yan; 3 S. Calder; 3 T. Guidi; 4 T. Perring; 4 R. W. McCallum; 2 T. A. Lograsso; 2 A. Kreyssig; 2 A. I. Goldman; 2; R. J. McQueeney1; 2 1; 3; 4

doi:10.1103/physrevb.87.140509

arXiv · 1303.4033

Two-dimensional magnetic interactions in LaFeAsO

M. Ramazanoglu·1·2 J. Lamsal·2 G. S. Tucker·2 J. -Q. Yan·3 S. Calder·3 T. Guidi·4 T. Perring·4 R. W. McCallum·2 T. A. Lograsso·2 A. Kreyssig·2 A. I. Goldman·2·R. J. McQueeney1·2 1·3·4

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Abstract

Inelastic neutron scattering measurements demonstrate that the magnetic interactions in antiferromagnetic LaFeAsO are two-dimensional. Spin wave velocities within the Fe layer and the magnitude of the spin gap are similar to the \textit{A}Fe$_2$As$_2$ based materials. However, the ratio of interlayer and intralayer exchange is found to be less than $\sim 10^{-4}$ in LaFeAsO, very similar to the cuprates, and $\sim$ 100 times smaller than that found in \textit{A}Fe$_2$As$_2$ compounds. The results suggest that the effective dimensionality of the magnetic system is highly variable in the parent compounds of the iron arsenides and weak 3-D interactions may limit the maximum attainable superconducting $T_{c}$.

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M. Ramazanoglu, 1, 2 J. Lamsal, 2 G. S. Tucker, 2 J. -Q. Yan, 3 S. Calder, 3 T. Guidi, 4 T. Perring, 4 R. W. McCallum, 2 T. A. Lograsso, 2 A. Kreyssig, 2 A. I. Goldman, 2, R. J. McQueeney1, 2 1, 3, 4. 2013-03-17. Two-dimensional magnetic interactions in LaFeAsO. https://doi.org/10.1103/physrevb.87.140509

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