Progress in Superconductivity and Cryogenics (한국초전도ㆍ저온공학회논문지)

The Korean Society of Superconductivity and Cryogenics (한국초전도저온학회)
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Normal-state charge dynamics of ternary platinum germanide superconductor La2Pt3Ge5

  • Song, S.J. (Department of Physics, Hanyang University) ;
  • Sung, N.H. (School of Materials Science and Applied Physics, Gwangju Institute of Science and Technology) ;
  • Cho, B.K. (School of Materials Science and Applied Physics, Gwangju Institute of Science and Technology) ;
  • Moon, S.J. (Department of Physics, Hanyang University)
  • Received : 2015.11.16
  • Accepted : 2015.12.23
  • Published : 2015.12.31
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Abstract

We report on the infrared spectroscopic studies of the normal-state electronic response of rare-earth ternary platinum germanide superconductor $La_2Pt_3Ge_5$. We analyzed the temperature-dependent optical conductivity spectra using the Drude-Lorentz oscillator model. We found that the two Drude responses with distinct scattering rates are required to explain the charge dynamics at 10 K while a single Drude mode could reproduce the far-infrared conductivity at higher temperatures. Our results indicated the two-band character of the electronic structure and highlighted the disparate temperature evolution of the electrodynamics of the two electronic states.

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References

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