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arXiv · 1206.5235

Evolution of the neutron resonances in AFe2Se2

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

Recent experiments on the alkali-intercalated iron selenides have raised questions about the symmetry of the superconducting phase. Random phase approximation calculations of the leading pairing eigenstate for a tight- binding 5-orbital Hubbard-Hund model of AFe2Se2 find that a d-wave (B1g) state evolves into an extended s{\pm} (A1g) state as the system is hole-doped. However, over a range of doping these two states are nearly degenerate. Here, we calculate the imaginary part of the magnetic spin susceptibility \chi"(q,{\omega}) for these gaps and discuss how the evolution of neutron scattering resonances can distinguish between them.

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T. A. Maier, P. J. Hirschfeld, D. J. Scalapino. 2012-06-22. Evolution of the neutron resonances in AFe2Se2. https://doi.org/10.1103/physrevb.86.094514

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