Progress in Superconductivity

The Korean Superconductivity Society (한국초전도학회)
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Superconducting and Magnetic Properties of the $(Ru_{1-x}Ta_x)Sr_2(Gd_{1.4}Ce_{0.6})Cu_2O_z$ System

$(Ru_{1-x}Ta_x)Sr_2(Gd_{1.4}Ce_{0.6})Cu_2O_z$ 계의 초전도 및 자기적 특성

  • Received : 2012.03.02
  • Accepted : 2012.03.30
  • Published : 2012.04.30
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Abstract

The effects of Ta substitution on the superconducting and magnetic properties of the $(Ru_{1-x}Ta_x)Sr_2(Gd_{1.4}Ce_{0.6})Cu_2O_z(0{\leq}x{\leq}0.5)$ system have been investigated. The X-ray diffraction measurements indicate that the Ta ion replaces Ru sites up to x = 0.4. It is found that the Ta substitution for Ru significantly reduces the weak-ferromagnetic component of the field-cooled magnetic susceptibility without an appreciable change of room temperature thermopower at lower Ta doping level below x = 0.2. The resistive transition temperature tends to decrease monotonically from 27 K for the x = 0 sample to 16 K (9 K) for the x = 0.4 (x = 0.5) sample. These results suggest that superconductivity of the $(Ru_{1-x}Ta_x)Sr_2(Gd_{1.4}Ce_{0.6})Cu_2O_z$ compound is not significantly affected by the magnetic state of the Ru sublattice. The experimental results are discussed in connection with previous reports on the effects of Nb substitution.

Keywords

References

  1. E. B. Sonin and I. Felner, "Spontaneous vortex phase in a superconducting weak ferromaghet", Phys. Rev. B57, R14000-R14003 (1998) https://doi.org/10.1103/PhysRevB.57.R14000
  2. I. Felner, U. Asaf, Y. Levi and O. Millo, "Coexistence of magnetism and superconductivity in $R_{1.4}Ce_{0.6} $. $RuSr_2Cu_2O_{10-\delta}$(R = Eu and Gd)", Phys. Rev. B55, 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 $RuSr_2GdCu_2O_8$ studied by muon spin rotation and dc magnetization", Phys. Rev. B 59, 14099-14107 (1999). https://doi.org/10.1103/PhysRevB.59.14099
  4. H. K. Lee and Y. C. Kim, "Superconducting and magnetic properties of ($Ru_{1-x}Nb_x$)$Sr_2$ ($Eu_{1.5}Ce_{0.5}$) $Cu_2O_z$", Int. J. Mod. Phys. B 17, 3682-3687 (2003). https://doi.org/10.1142/S0217979203021617
  5. H. K. Lee and G. V. M. Williams, "Effect of Nb doping on superconducting and magnetic properties of$RuSr_2$($Gd_{1.5-y}Eu_yCe_{0.5}$)$Cu_2O_z$", Physica C 415, 172-178 (2004). https://doi.org/10.1016/j.physc.2004.08.012
  6. V. P. S. Awana, R. Lal, H. Kishan, A. V. Narlikar, M. Peurla and R.Laiho, "Experimental study of the magnetosuperconductor $RuSr_2Eu_{1.5}Ce_{0.5}Cu_2O_{10-\delta}$: Effect of Mo doping on magnetic behavior and $T_c$ variation", Phys. Rev. B 73, 014517(1)-014517(6) (2006).
  7. I. Felner and U. Asaf, "Superconductivity and weak ferromagnetism in $Eu_{1.4}Ce_{0.6}Ru_{1-x}Fe_xSr_2Cu_2O_{10-\delta}$", Physica C 292, 97-103 (1997). https://doi.org/10.1016/S0921-4534(97)01673-0
  8. V. P. S. Awana, H. Kishan, O. Eshkenazi, I. Felner, Rajeev Rawat, V. Ganesan and A. V. Narlikar, "Experimental study of magneto-superconductor $RuSr_2Eu_{1.5}Ce_{0.5}Cu_2O_{10-\delta}$: peculiar effect of Co doping on complex magnetism and Tc variation", J. Phys: Condens. Matter 19, 026203(1)-026203(14) (2007).
  9. N. Balchev, K. Nenkov, G. Mihova, B. Kunev and J. Pirov, "Superconducting and magnetic properties of Sn-doped Ru-1222", Physica C 467, 174-178 (2007). https://doi.org/10.1016/j.physc.2007.10.008
  10. L. Shi, G. Li, Y. Pu, X. D. Zhang, S. J. Feng and X.-G. Li, "Effect of Pb doping on the superconducting and magnetic resonance properties of Ru-1222", Materials Letters 57, 3919-3923 (2003). https://doi.org/10.1016/S0167-577X(03)00241-6
  11. C. A. Cardoso, F. M. Araujo-Moreira, V. P. S. Awana, H. Kishan and O. F. de Lima, "Study of the superconducting and magnetic properties of niobium doped $RuSr_2Gd_{1.5}Ce_{0.5}Cu_2O_{10-\delta}$ ruthenocuprates", Physica C 460-462, 442-443 (2007). https://doi.org/10.1016/j.physc.2007.03.114
  12. S. K. Goh, G. V. M. Williams and H. K. Lee, "The effect of substituents on magnetic order and superconductivity in $RuSr_2R_{2-y}Ce_yCu_2O_{10+\delta}$(R = Eu, Gd)", Current Appl. Phys. 6, 515-519 (2006). https://doi.org/10.1016/j.cap.2005.11.052
  13. H. K. Lee, "Superconductivity in the (Pb,V)Sr2 (Ca,Tb)$Cu_2Oz$ system", J. Korean Phys. Soc. 36, 384-386 (2000).
  14. R. D. Shannon, "Revised Effective Radii and Systematic studies of interatomic distances in halides and chalcogenides", Acta Cryst. A 32, 751-767 (1976). https://doi.org/10.1107/S0567739476001551
  15. J. L. Tallon, C. Bernhard, H. Shaked, R. L. Hitterman and J. D. Jorgenson, "Generic superconducting phase behavior in High-Tc cuprates: Tc variation with hole concentration in $YBa_2Cu_3O_{7-Z}$", Phys. Rev. B51, 12911-12914 (1995). https://doi.org/10.1103/PhysRevB.51.12911
  16. J. L. Wagner, P. G. Radaelli, D. G. Hinks, J. D. Jorgensen, J. F. Mitchell, B. Dadrowski, G. S. Knapp and M. A. Beno, "Structure and superconductivity of $HgBa_2CuO_{4+\delta}$", Physica C 210, 447-454 (1993). https://doi.org/10.1016/0921-4534(93)90989-4