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.
@article{arxiv.cond-mat/0404558,
title = {Effect of Co-Ga paired substitution on superconductivity in YBa2Cu3O7-d},
author = {Anjana Dogra and S. Rayaprol and N. A. Shah and D. G. Kuberkar},
journal= {arXiv preprint arXiv:cond-mat/0404558},
year = {2009}
}