Research PapersNo Access

EFFECT OF Co–Ga PAIRED SUBSTITUTION ON SUPERCONDUCTIVITY IN YBa₂Cu₃O_7-δ

ANJANA DOGRA

Material Science Division, Nuclear Science Centre, New Delhi 110 067, India

Search for more papers by this author

S. RAYAPROL

DCMP & MS, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India

Corresponding author.

Search for more papers by this author

N. A. SHAH

Department of Electronics, Saurashtra University, Rajkot 360 005, India

Search for more papers by this author

, and

D. G. KUBERKAR

Department of Physics, Saurashtra University, Rajkot 360 005, India

Search for more papers by this author

https://doi.org/10.1142/S0217984904007025Cited by:0 (Source: Crossref)

Abstract

The effect of Co–Ga paired substitution on the superconducting properties of YBa₂Cu₃O_7-δ (Y-123) has been investigated by X-ray diffraction, ac susceptibility, dc resistivity and oxygen content measurements. We report in this paper the results of our studies on the paired substitution of a magnetic and non-magnetic ion at Cu site in Y-123, while keeping the total dopant concentration fixed. The simultaneous substitution of Co and Ga at Cu site shows variation in the transition temperature (T_c), oxygen content and hole concentration as a function of change in the balance of magnetic (Co) and non-magnetic (Ga) concentration. Orthorhombicity (D), given as (b-a)/a, also varies as a function of increasing dopant concentration. The variation in T_c due to Co–Ga substitution is discussed in the light of dopant valency and hole filling mechanism.

Keywords:

References

J. M. Tarascon and B. G. Bagley, Chemistry of high temperature superconductors, ed. T. A. Vanderah (NOYES Publ., New York, 1993) p. 310. Google Scholar
A. V. Narlikar, S. K. Agarwal and C. V. Narasimha Rao, Studies of high temperature superconductors, ed. A. V. Narlikar (NOVA Sci. Publ., New York, 1989) p. 343. Google Scholar
B. Raveau et al. , Crystal Chemistry of High Tc Superconducting Copper Oxides , Springer Ser. in Mat. Sci. 15 ( Springer-Verlag , Berlin , 1992 ) . Google Scholar
T. Harada and K. Yoshida, Physica C 391, 1 (2003). Web of Science, ADS, Google Scholar
C. N. R. Rao (ed.) , Chemistry of Oxide superconductors ( Blackwell Sci. Publ. , Oxford, UK , 1988 ) . Google Scholar
C. P. Poole Jr. , T. Datta and H. A. Farach , Copper Oxide Superconductors ( Wiley-Interscience Publ. , USA ) . Google Scholar
T. A. Mary and U. V. Varadaraju, Mater. Res. Bull. 27, 447 (1992). Web of Science, Google Scholar
T. J. Kistenmacher, Phys. Rev. B 38, 8862 (1988). Web of Science, ADS, Google Scholar
R. S. Howlandet al., Phys. Rev. B 39, 9017 (1989). Web of Science, ADS, Google Scholar
R. Aokiet al., Physica C 156, 405 (1988). Web of Science, ADS, Google Scholar
E. Dagotto, Rev. Mod. Phys. 66, 763 (1994). Web of Science, ADS, Google Scholar
D.-N. Shi and Z.-Z. Li, Physica C 270, 274 (1996). Web of Science, ADS, Google Scholar
I. M. Tang, S. Leelaprute and P. Winotai, Physica C 312, 321 (1999). Web of Science, ADS, Google Scholar
D. A. Wollmanet al., Phys. Rev. Lett. 71, 2134 (1993). Web of Science, ADS, Google Scholar
A. I. Nazzalet al., Physica C 153–155, 1367 (1988). Web of Science, ADS, Google Scholar
Y. Xuet al., Phys. Rev. B 38, 7084 (1988). Web of Science, ADS, Google Scholar