title: Evidence of a spin resonance mode in the iron-based superconductor Ba(0.6)K(0.4)Fe2As2 from scanning tunneling spectroscopy.
abstract: We used high-resolution scanning tunneling spectroscopy to study the hole-doped iron pnictide superconductor Ba(0.6)K(0.4)Fe(2)As(2) (T(c)=38 K). Features of a bosonic excitation (mode) are observed in the measured quasiparticle density of states. The bosonic features are intimately associated with the superconducting order parameter and have a mode energy of ~14 meV, similar to the spin resonance measured by inelastic neutron scattering. These results indicate a strong electron-spin excitation coupling in iron pnictide superconductors, similar to that in high-T(c) copper oxide superconductors.
authors.affiliation: National Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China. lshan@aphy.iphy.ac.cn
authors.forename: Lei
authors.initials: L
authors.lastname: Shan
authors.forename: Jing
authors.initials: J
authors.lastname: Gong
authors.forename: Yong-Lei
authors.initials: YL
authors.lastname: Wang
authors.forename: Bing
authors.initials: B
authors.lastname: Shen
authors.forename: Xingyuan
authors.initials: X
authors.lastname: Hou
authors.forename: Cong
authors.initials: C
authors.lastname: Ren
authors.forename: Chunhong
authors.initials: C
authors.lastname: Li
authors.forename: Huan
authors.initials: H
authors.lastname: Yang
authors.forename: Hai-Hu
authors.initials: HH
authors.lastname: Wen
authors.forename: Shiliang
authors.initials: S
authors.lastname: Li
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Dai