Progress in Superconductivity

The Korean Superconductivity Society (한국초전도학회)
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A Novel Method for Measurements of the Penetration Depth of $MgB_2$ Superconductor Films by Using Sapphire Resonators with Short-Circuited Parallel Plates

Short-Circuited 평행판 사파이어 공진기를 이용한 $MgB_2$ 초전도체 박막의 침투깊이 측정법

  • Jung, Ho-Sang (Department of Physics, Konkuk University) ;
  • Lee, J.H. (Department of Physics, Konkuk University) ;
  • Cho, Y.H. (Department of Physics, Konkuk University) ;
  • Seong, W.K. (Department of Physics, Sungkyunkwan University) ;
  • Lee, N.H. (Department of Physics, Sungkyunkwan University) ;
  • Kang, W.N. (Department of Physics, Sungkyunkwan University) ;
  • Lee, Sang-Young (Department of Physics, Konkuk University)
  • Published : 2009.04.30
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Abstract

We introduce a measurement method that enables to measure the penetration depth($\lambda$) of superconductor films by using a short-ended parallel plate sapphire resonator. Variations in the $\lambda$ of $MgB_2$ films could be measured down to the lowest temperature using a sapphire resonator with a $YBa_2Cu_3O_{7-x}$ film at the bottom. A model equation of $\lambda=\lambda_0[1-(T/T_c)^{\tau}]^{-1/2}$ for $MgB_2$ films appeared to describe the observed variations of the resonant frequency of the sapphire resonator with temperature, with $\lambda_0,\;\tau$, and $T_C$ used as the fitting parameters.

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References

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