Progress in Superconductivity

The Korean Superconductivity Society (한국초전도학회)
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Structure and Superconducting Properties of Ba-substituted (Ru,Cu)(Sr,Eu)$_2$(Eu,Ce)$_2Cu_2O_z$ System

Ba 치환에 따른 (Ru,Cu)(Sr,Eu)$_2$(Eu,Ce)$_2Cu_2O_z$ 계의 초전도 특성

  • Received : 2011.07.01
  • Accepted : 2011.07.27
  • Published : 2011.08.31
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Abstract

We investigated the effects of Ba and Cu co-substitution on the structural and superconducting properties of ($Ru_{1-y}Cu_y$)($Sr_{1.67-x}Ba_xEu_{0.33}$)($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$ samples. X-ray diffraction(XRD) reveals that single-phase samples can be obtained in the range from x = 0.1 to 0.2 for ($Ru_{0.5}Cu_{0.5}$)($Sr_{1.67-x}Ba_xEu_{0.33}$)($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$ and from y = 0.25 to 0.5 for ($Ru_{1-y}Cu_y$)($Sr_{1.47}Ba_{0.2}Eu_{0.33}$)($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$, respectively. All samples with compositions of ($Ru_{0.5}Cu_{0.5}$)($Sr_{1.67-x}Ba_xEu_{0.33}$) ($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$ (x = 0 - 0.33) show superconducting transition behavior and the onset transition temperature decreases slightly with increasing x in consistent with the change of hole concentration estimated from room temperature thermoelectric power measurements. The XRD and resistivity measurements for the ($Ru_{1-y}Cu_y$)($Sr_{1.47}Ba_{0.2}Eu_{0.33}$)($Eu_{1.34}Ce_{0.66}$) $Cu_2O_z$ system indicate that the partial substitution of Cu for Ru is necessary to form phase pure samples, but result in a small change in transition temperature in the single-phase region from x = 0.25 to 0.5.

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References

  1. L. Bauernfeind, W. Widder and H. F. Braun, "Ruthenium-based layered cuprates $RuSr_{2}LnCu_{2}O_{8}$ and $RuSr_{2}$($Ln_{1+x}Ce_{1-x}$)$Cu_{2}O_{10}$(Ln = Sm, Eu and Gd)", Physica C 254, 151 - 158 (1995). https://doi.org/10.1016/0921-4534(95)00574-9
  2. I. Felner, U. Asaf, Y. Levi, O. Millo, "Coexistence of magnetism and superconductivity in $R_{1.4}Ce_{0.6}.RuSr_{2}Cu_{2}O_{10-\delta}$ (R=Eu and Gd)", Phys. Rev. B 55, R3374-R3377 (1997). https://doi.org/10.1103/PhysRevB.55.R3374
  3. C. Bernhard, J. L. Tallon, Ch. Niedermayer, Th. Blasius, A. Golnik, E. Brucher, R. K. Kremer, D. R. Noakes, C. E. Stronach and E. J. Ansaldo, "Coexistence of ferromagnetism and superconductivity in the hybrid ruthenate-cuprate compound $RuSr_{2}GdCu_{2}O_{8}$ studied by muon spin rotation and dc magnetization", Phys. Rev. B 59, 14099-14107 (1999). https://doi.org/10.1103/PhysRevB.59.14099
  4. J. D. Jorgensen, O. Chmaissem, H. Shaked, S. Short, P. W. Klamut, P. W. Dabroski and J. L. Tallon, "Magnetic ordering in the superconducting weak ferromagnets $RuSr_{2}GdCu_{2}O_{8}$ and $RuSr_{2}EuCu_{2}O_{8}$", Phys. Rev. B 63, 054440(1) - 054440(5) (2001).
  5. J. W. Lynn, Y. Chen, Q. Huang, S. K. Goh and G. V. M. Williams, "Search for magnetic order in superconducting $RuSr_{2}Eu_{1.2}Ce_{0.8}Cu_{2}O_{10}$", Phys. Rev. B 76, 014519(1)-014519(8) (2007).
  6. H. K. Lee, J. M .Lee and Y. I. Kim, "Synthesis and superconductivity in Ba-doped $(Ru,Cu)(Sr,Nd)_{2}(Nd,Ce)_{2}Cu_{2}O_{z}$ compounds", J. Supercond. Nov. Magn. 23, 629-632 (2010). https://doi.org/10.1007/s10948-010-0721-0
  7. H. K. Lee and Y. I. Kim, unpublished.
  8. H. K. Lee, "Effect of Cu substitution on superconductivity in $(Ru_{1-x}Cu_{x})Sr_{2}(Eu_{1.34}Ce_{0.66})Cu_{2}O_{z}$ system", Progress in Superconductivity 11, 67-71 (2009).
  9. B. Fisher, J. Genossac, C. G. Kuper, L. Patlagan, G. M. Reisner and A. Knizhnik, "Effect of substituting calcium for yttrium on the properties of $YBa_{2}Cu_{3}O_{7-\delta}$", Phys. Rev. B 47, 6054-6059 (1993). https://doi.org/10.1103/PhysRevB.47.6054