Optical properties of the iron-chalcogenide superconductor FeTe0.55Se0.45

Autor: Homes, Christopher C., Akrap, Ana, Wen, Jinsheng, Xu, Zhijun, Lin, Zhi Wei, Li, Qiang, Gu, Genda
Rok vydání: 2010
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1016/j.jpcs.2010.10.014
Popis: The complex optical properties of the iron-chalcogenide superconductor FeTe0.55Se0.45 with Tc=14K have been examined over a wide frequency range for light polarized in the Fe-Te(Se) planes above and below Tc. At room temperature the optical response may be described by a weakly-interacting Fermi liquid; however, just above Tc this picture breaks down and the scattering rate takes on a linear frequency dependence. Below Tc there is evidence for two gap features in the optical conductivity at Delta_1 ~ 2.5 meV and Delta_2 ~ 5.1 meV. Less than 20% of the free carriers collapse into the condensate for T << Tc, and this material is observed to fall on the universal scaling line for a BCS dirty-limit superconductor in the weak-coupling limit.
Comment: 6 pages, 6 figures; accepted J. Phys. Chem. Solids, proceedings of SNS2010 in Shanghai (updated references)
Databáze: arXiv