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تسجيل مستخدم جديدResonance, Fermi surface topology, and Superconductivity in Cuprates
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The resonance, a collective boson mode, was usually thought to be a possible glue of superconductivity. We argue that it is rather a natural product of the emph{d}-wave pairing and the Fermi surface topology. A universal scaling $E_{res}/2Delta ^{H}_{S}sim 1.0$ ($Delta_{S}^{H}$ the magnitude of superconducting gap at hot spot) is proposed for cuprates, irrespective of the hole-/electron-doping, low-/high-energy resonance, monotonic/nonmonotonic emph{d}-wave paring, and the parameters selected. We reveal that there may exist two resonance peaks in the electron-doped cuprates. The low- and high- energy resonance, originated from the contributions of the different intra-band component, is intimately associated with the Fermi surface topology. By analyzing the data of inelastic neutron scattering, we conclude the nonmonotonic emph{d}-wave superconducting pairing symmetry in the electron-doped cuprates, which is still an open question
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