Heat treatment-induced changes in structural and superconducting properties of (Y1−xSmx)1−yEuyBaSrCu3O6+z compounds

This study provides new experimental insights into the structural and superconducting properties of (Y 1−x Sm x ) 1−y Eu y BaSrCu 3 O 6+z compounds. The effects of two annealing procedures oxygen ([O]) and successive argon–oxygen ([AO]) treatments were systematically investigated for varying Sm and Eu contents. The AO treatment generally increases orthorhombicity and enhances the critical temperature (Tc) in Sm-substituted samples, whereas YBaSrCu 3 O 6+z exhibits a slight reduction in Tc. These results emphasize the correlation between lattice parameter variations, oxygen ordering in the Cu(1)O plane, and superconducting properties. Overall, the findings extend previously reported trends relating structural parameters, oxygen order, and hole concentration to Tc to Sm and Eu substituted compositions.