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arXiv · 1103.0688

Inelastic neutron and x-ray scattering as probes of the sign structure of the Fe-pnictide superconducting gap

T. A. Maier·S. Graser·P. J. Hirschfeld·D. J. Scalapino
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Abstract

Neutron spin-flip scattering observations of a resonance in the superconducting state is often taken as evidence of an unconventional superconducting state in which the gap changes sign $Δ(k+Q)=-Δ(k)$ for momentum transfers $Q$ which play an important role in the pairing. Recently questions regarding this identification for the Fe-pnictide superconductors have been raised and it has been suggested that $Δ(k+Q)=Δ(k)$. Here we propose that inelastic neutron or x-ray scattering measurements of the spectral weight of a phonon of momentum $Q$ can distinguish between these two pairing scenarios.

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T. A. Maier, S. Graser, P. J. Hirschfeld, D. J. Scalapino. 2011-03-03. Inelastic neutron and x-ray scattering as probes of the sign structure of the Fe-pnictide superconducting gap. https://doi.org/10.1016/j.physc.2011.08.004

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