Implications of simultaneous doping at plane and chain copper sites in Y 1Ba 2Cu 3O 7−δ system for its superconducting properties

Abstract

Recently we reported that codoping of Fe (chain dopant) and Zn (plane dopant) in Y 1Ba 2Cu 3O 7−δ leads to a giant Tc depression as compared to the cases of separate doping of either impurities at the same total concentration. In this work we have examined additional cases of codoping of Fe and Zn as well as Ga and Zn. Specifically, the dependence of Tc on the total concentration x in Y 1Ba 2Cu 3−xZn yM x−y (M = Fe or Ga, y = 0.1 fixed, x>0.1) is studied. Similarly, for a fixed concentration of 0.1 of Fe or Ga, the dependence of Tc on the increasing concentration of Zn is examined. The systematics reflect a correlation between Tc dependence and ortho/tetra structural transformation features.