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Effect of Co-Ga paired substitution on superconductivity in YBa2Cu3O7-d

Anjana Dogra·S. Rayaprol·N. A. Shah·D. G. Kuberkar
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Abstract

The effect of Co-Ga paired substitution on the superconducting properties of YBa2Cu3O7-d (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 (Tc), 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 Tc due to Co-Ga substitution is discussed in the light of dopant valency and hole filling mechanism.

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Anjana Dogra, S. Rayaprol, N. A. Shah, D. G. Kuberkar. 2004-04-23. Effect of Co-Ga paired substitution on superconductivity in YBa2Cu3O7-d. https://doi.org/10.1142/s0217984904007025

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