• 제목/요약/키워드: BCS coupling constant

검색결과 2건 처리시간 0.014초

Zn로 치환된 MgCN $i_3$의 초전도 특성 (Superconducting property in the Zn substituted MgC$Ni_3$)

  • 이용우;김진수;박민석;이성익;심지훈;민병일;최은집
    • Progress in Superconductivity
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    • 제4권2호
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    • pp.144-147
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    • 2003
  • We investigated superconducting property of ($Mg_{1-x}$$Zn_{x}$)$CNi_3$ (x=0,0.03, 0.06, 0.09, 0.12, 0.15, and 0.18) sample where Mg is substituted with Zn. The samples were synthesized us ins the solid state reaction method under As atmosphere. X -ray diffraction spectra show that the $MgCNi_3$ structure is maintained up to x=18. With increasing x, the lattice constant (or the Ni-Ni distance) decreases. Magnetic susceptibility measurement shows that $T_{c}$ decreases systematically with x and becomes ~2K at x =0.18. Surprisingly, the transition width remains sharp (~0.3K). Under some assumptions, we estimate the coupling constant in the McMillan formula as a function of x which we interpret in terms of the BCS theory.y.y.y.

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