2008/07/07 by Jerry Zhijian Yang, J. Yang, D. Huvonen +12 · 1 citation
Materials Science · Physics and Astronomy · #Atomic physics #Condensed matter physics #Coupling (piping) #Cuprate #Iron-based superconductors research #Materials science #Optical conductivity #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Scattering #Scattering rate #Spectroscopy #Superconductivity #Superconductivity in MgB2 and Alloys #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.102.187003
4 pages, 4 figures
arxiv created 2008/07/07 · openalex publication_date 2009/05/05 · arxiv updated 2013/05/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Normal state optical spectroscopy on single crystals of the new iron arsenide superconductor Ba0.55K0.45Fe2As2 shows that the infrared spectrum consists of two major components: a strong metallic Drude band and a well-separated midinfrared absorption centered at 0.7 eV. It is difficult to separate the two components unambiguously but several fits using Lorentzian peaks suggest a model with a Drude peak having a plasma frequency of 1.6 to 2.1 eV and a midinfrared peak with a plasma frequency of 2.5 eV. Detailed analysis of the frequency dependent scattering rate shows that the charge carriers interact with a broad bosonic spectrum extending beyond 100 meV with a very large coupling constant lambda=3.4 at low temperature. As the temperature increases this coupling weakens to lambda=0.78 at ambient temperature. This suggests a bosonic spectrum that is similar to what is seen in the lower Tc cuprates.