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arXiv · 1304.6657

Magnonlike dispersion of spin resonance in Ni-doped BaFe$_2$As$_2$

M. G. Kim·G. S. Tucker·D. K. Pratt·S. Ran·A. Thaler·A. D. Christianson·K. Marty·A. Podlesnyak·S. L. Bud'ko·P. C. Canfield·A. Kreyssig·A. I. Goldman·R. J. McQueeney
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Abstract

Inelastic neutron scattering measurements on Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ manifest a neutron spin resonance in the superconducting state with anisotropic dispersion within the Fe layer. Whereas the resonance is sharply peaked at Q$_{AFM}$ along the orthorhombic a axis, the resonance disperses upwards away from Q$_{AFM}$ along the b axis. In contrast to the downward dispersing resonance and hour-glass shape of the spin excitations in superconducting cuprates, the resonance in electron-doped BaFe$_2$As$_2$ compounds possesses a magnon-like upwards dispersion.

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M. G. Kim, G. S. Tucker, D. K. Pratt, S. Ran, A. Thaler, A. D. Christianson, K. Marty, A. Podlesnyak, S. L. Bud'ko, P. C. Canfield, A. Kreyssig, A. I. Goldman, R. J. McQueeney. 2013-04-24. Magnonlike dispersion of spin resonance in Ni-doped BaFe$_2$As$_2$. https://doi.org/10.1103/physrevlett.110.177002

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