High-TcTc superconductivity in the LaFeAsO1−xFx system based on inelastic neutron scattering measurements

Dynamical spin susceptibility χ″(q,ω)χ″(q,ω) of the LaFeAsO1−xFx system is discussed based on the itinerant picture. The spin resonant energy relative to the superconducting transition temperature is compared with those of other iron-based superconductors, and discussed in relation to the anomalous phonon mode of Y Ni2B2C. Phase diagrams of iron-based and copper oxide superconductors are discussed in terms of chemical bonding characters. Possible lattice breathing by the electron round scattering between hole and electron Fermi surfaces is proposed from the chemical point of view.

► Dynamical spin susceptibility of the LaFeAsO1−xFx system is discussed.
► The spin resonant energy is compared with those of other iron-based superconductors.
► Phase diagrams of iron-based and copper oxide superconductors are discussed.
► Possible lattice breathing is proposed from the chemical point of view.