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arXiv · 1002.3350

Dispersion of the superconducting spin resonance in underdoped and antiferromagnetic Ba(Fe1-xCox)2As2

D. K. Pratt·A. Kreyssig·S. Nandi·N. Ni·A. Thaler·M. D. Lumsden·W. Tian·J. L. Zarestky·S. L. Bud'ko·P. C. Canfield·A. I. Goldman·R. J. McQueeney
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Abstract

Inelastic neutron scattering measurements have been performed on underdoped Ba(Fe1-xCox)2As2 (x = 4.7%) where superconductivity and long-range antiferromagnetic (AFM) order coexist. The broad magnetic spectrum found in the normal state develops into a magnetic resonance feature below TC that has appreciable dispersion along c-axis with a bandwidth of 3-4 meV. This is in contrast to the optimally doped x = 8.0% composition, with no long-range AFM order, where the resonance exhibits a much weaker dispersion [see Lumsden et al. Phys. Rev. Lett. 102, 107005 (2009)]. The results suggest that the resonance dispersion arises from interlayer spin correlations present in the AFM ordered state.

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D. K. Pratt, A. Kreyssig, S. Nandi, N. Ni, A. Thaler, M. D. Lumsden, W. Tian, J. L. Zarestky, S. L. Bud'ko, P. C. Canfield, A. I. Goldman, R. J. McQueeney. 2010-02-17. Dispersion of the superconducting spin resonance in underdoped and antiferromagnetic Ba(Fe1-xCox)2As2. https://doi.org/10.1103/physrevb.81.140510

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