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arXiv · 1205.0352

Evidence of a spin resonance mode in the iron-based superconductor Ba$_{0.6}$K$_{0.4}$Fe$_{2}$As$_{2}$ from scanning tunneling spectroscopy

Lei Shan·Jing Gong·Yong-Lei Wang·Bing Shen·Xingyuan Hou·Cong Ren·Chunhong Li·Huan Yang·Hai-Hu Wen·Shiliang Li·Pengcheng Dai
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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 $\sim$14 meV, similar to the spin resonance measured by inelastic neutron scattering. These results indicate a strong electron-spin excitation coupling in iron pictnide superconductors, similar to that in high-$T_c$ copper oxide superconductors.

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Lei Shan, Jing Gong, Yong-Lei Wang, Bing Shen, Xingyuan Hou, Cong Ren, Chunhong Li, Huan Yang, Hai-Hu Wen, Shiliang Li, Pengcheng Dai. 2012-05-02. Evidence of a spin resonance mode in the iron-based superconductor Ba$_{0.6}$K$_{0.4}$Fe$_{2}$As$_{2}$ from scanning tunneling spectroscopy. https://doi.org/10.1103/physrevlett.108.227002

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