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arXiv · 0903.0008

Neutron Scattering Resonance and the Fe-pnictide Superconducting Gap

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

The existence of a neutron scattering resonance at a wavevector q* implies a sign change of the gap between two Fermi surface regions separated by wavevector q* . For the Fe pnictides, a resonance has been observed for a wavevector q* which connects a hole Fermi surface around the $Γ$ point with an electron Fermi surface around the X or Y points of the 1 Fe/unit cell Brillouin zone. Here we study the neutron scattering resonance for a five orbital model within an RPA-BCS approximation. Our results show that both sign-switched and extended s-wave gaps are consistent with the present data for q* near ($π$, 0) and that scattering at other momentum transfers can be useful in distinguishing between gap structures.

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T. A. Maier, S. Graser, D. J. Scalapino, P. Hirschfeld. 2009-02-28. Neutron Scattering Resonance and the Fe-pnictide Superconducting Gap. https://doi.org/10.1103/physrevb.79.134520

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