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Effect of Cation Substitution on the Lattice Vibration and Crystal Structure of Magnetic RuSr1.9A0.1GdCu2O8 (A = Ca, Sr, and Ba) Superconductors

  • Kim, Tae-Woo (Center for Intelligent Nano-Bio Materials (CINBM), Department of Chemistry and Nano Sciences, Ewha Womans University) ;
  • Yang, In-Sang (Department of Physics, Ewha Womans University) ;
  • Hwang, Seong-Ju (Center for Intelligent Nano-Bio Materials (CINBM), Department of Chemistry and Nano Sciences, Ewha Womans University)
  • Published : 2009.11.20

Abstract

The lattice vibration and crystal structure of alkaline earth metal-substituted $RuSr_{1.9}A_{0.1}GdCu_{2}O_{8}$ (A = Ca, Sr, and Ba) have been investigated with micro-Raman spectroscopy. The present $RuSr_{1.9}A_{0.1}GdCu_{2}O_{8}$ materials show not only several weak Raman peaks corresponding to the vibrations of $O_{Cu}$ and $O_{Ru}$ but also strong characteristic phonon lines related to $O_{Sr}$ vibration mode. A comparison between the frequency of $O_{Sr}$ vibration and the bond distances of (Ru$O_{Sr}$) and (Cu‒$O_{Sr}$) in the present ruthenocuprates reveals that the vibration energy of $O_{Sr}$ is mainly dependent on the bond distance of (Ru‒$O_{Sr}$). The peak splitting of the $O_{Sr}$ phonon lines was observed for the unsubstituted $RuSr_{1.9}A_{0.1}GdCu_{2}O_{8}$, suggesting the existence of two different (Ru‒$O_{Sr}$) bond distances. Such a peak splitting caused by the appearance of low-energy shoulder reflects the presence of internal charge transfer pathway from the $RuO_2$ plane to the superconductive $CuO_2$ one. After the substitution of Sr with Ca or Ba, the low-energy shoulder peak of $O_{Sr}$ vibration becomes suppressed, underscoring the depression of internal charge transfer between the $RuO_2$ and $CuO_2$ planes. The weakened role of $RuO_2$ layer as charge reservoir in the $RuSr_{1.9}A_{0.1}GdCu_{2}O_{8}$8 (A = Ca, Ba) would be responsible for the depression of $T_c$ upon the Ca/Ba substitution.

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References

  1. Bauernfeind, L.; Wider, W.; Braun, H. F. Physica C 1995, 254, 151 https://doi.org/10.1016/0921-4534(95)00574-9
  2. Tallon, J. L.; Bernhard, C.; Bowden, M. E.; Gilberd, P. W.; Stoto, T. M.; Pringle, D. J. IEEE Trans. Appl. Supercond. 1999, 9, 1696 https://doi.org/10.1109/77.784779
  3. Williams, G. V. M.; Kramer, S. Phys. Rev. B 2000, 62, 4132 https://doi.org/10.1103/PhysRevB.62.4132
  4. Chmaissem, O.; Jorgensen, J. D.; Shaked, H.; Dollar, P.; Tallon, J. L. Phys. Rev. B 2000, 61, 6401 https://doi.org/10.1103/PhysRevB.61.6401
  5. Picket, W. E.; Weht, R.; Shick, A. B. Phys. Rev. Lett. 1999, 83, 3713 https://doi.org/10.1103/PhysRevLett.83.3713
  6. Nakamura, K.; Freeman, A. J. Phys. Rev. B 2002, 66, 140405 https://doi.org/10.1103/PhysRevB.66.140405
  7. Hur, S. G.; Park, D. H.; Hwang, S.-J.; Kim, S. J.; Lee, J. H.; Lee, S. Y. J. Phys. Chem. B 2005, 109, 21694 https://doi.org/10.1021/jp054770e
  8. Hur, S. G.; Park, D. H.; Hwang, S.-J.; Kim, S. J.; Lee, J. H.; Lee, S. Y. J. Phys. Chem. B 2005, 109, 9239 https://doi.org/10.1021/jp044611f
  9. Hur, S. G.; Hwang, S.-J. J. Kor. Chem. Soc. 2005, 49, 78 https://doi.org/10.5012/jkcs.2005.49.1.078
  10. Liu, R. S.; Jang, L. Y.; Hung, H. H.; Tallon, J. L. Phys. Rev. B 2001, 63, 212507 https://doi.org/10.1103/PhysRevB.63.212507
  11. Fainstein, A.; Etchegoin, P.; Trodahl, H. J.; Tallon, J. L. Phys. Rev. B 2000, 61, 15468 https://doi.org/10.1103/PhysRevB.61.15468
  12. Fainstein, A.; Pantoja, A. E.; Trodahl, H. J.; McCrone, J. E.; Cooper, J. R.; Gibson, G.; Barber, Z.; Tallon, J. L. Phys. Rev. B 2001, 63, 144505 https://doi.org/10.1103/PhysRevB.63.144505
  13. Williams, G. V. M.; Ryan, M. Phys. Rev. B 2001, 64, 094515 https://doi.org/10.1103/PhysRevB.64.094515
  14. Iliev, M. N.; Litvinchuk, A. P.; Popov, V. N.; Meng, R. L.; Dezaneti, JL. M.; Chu, C. W. Physica C 2000, 341-348, 2209 https://doi.org/10.1016/S0921-4534(00)00990-4
  15. Kim, J. E.; Hwang, C.-S.; Yoon, S. Bull. Kor. Chem. Soc. 2008, 29, 1247 https://doi.org/10.5012/bkcs.2008.29.6.1247
  16. Tallon, J. L.; Loram, J. W.; Williams, G. W. M.; Bernhard, C. Phys. Rev. B 2000, 61, R6471 https://doi.org/10.1103/PhysRevB.61.R6471
  17. Pozek, M.; Dulcic, A.; Paar, D.; Williams, G. V. M.; Kramer, S. Phys. Rev. B 2001, 64, 064508 https://doi.org/10.1103/PhysRevB.64.064508

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