2008/04/30 by M. M. Korshunov, Ilya Eremin, I. Eremin · 6 citations
Business, Management and Accounting · Materials Science · Physics and Astronomy · #Corporate Taxation and Avoidance #Iron-based superconductors research #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.78.140509
published as Phys. Rev. B 78, 140509(R) (2008) · 5 pages, 3 figures, published version
openalex publication_date 2008/10/24 · arxiv created 2008/10/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Based on the effective four-band model we analyze the spin response in the normal and superconducting states of the Fe-pnictide superconductors. While the normal-state spin excitations are dominated by the continuum of the interorbital antiferromagnetic fluctuations and the intraband spin-density wave fluctuations, the unconventional superconductivity yields different feedback. The resonance peak in the form of the well-defined spin exciton occurs only for the interband scattering at the antiferromagnetic momentum QAFM for the s_\ifmmode±\else\textpm\fi (extended s wave) superconducting order parameter and it disappears rapidly for q<QAFM. The resonance feature is extremely weak for the d_x2\ensuremath-y2-wave order parameter due to the specific Fermi-surface topology of these compounds. The essential difference between s_\ifmmode±\else\textpm\fi-wave and d_x2\ensuremath-y2-wave symmetries for the magnetic excitations can be used for experimental determination of the superconducting wave-function symmetry.