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arXiv · 1007.1447

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

Christopher C. Homes·Ana Akrap·Jinsheng Wen·Zhijun Xu·Zhi Wei Lin·Qiang Li·Genda Gu
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Abstract

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.

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Christopher C. Homes, Ana Akrap, Jinsheng Wen, Zhijun Xu, Zhi Wei Lin, Qiang Li, Genda Gu. 2010-07-08. Optical properties of the iron-chalcogenide superconductor FeTe0.55Se0.45. https://doi.org/10.1016/j.jpcs.2010.10.014

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