Homogeneous distribution of carriers in the conducting planes by Zn substitution at Cu sites in Cu0.5Tl0.5Ba2Ca3Cu4O12−δ superconductors

Abstract

The effect of suppression of antiferromagnetic order and charge stripes formation mechanism, by Zn3d 10 (S = 0) substitution at Cu3d 9 (S = 1/2) sites in CuO 2 planes of Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12-δ , on superconductivity parameters is demonstrated. If antiferromagnetism and charge stripes have some role in bringing about superconductivity at a particular temperature, the doping of nonmagnetic Zn impurity would destroy it and hence the superconductivity. However we have observed enhanced superconducting properties with the increase of Zn doping in Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12-δ superconductor. The decreased c-axis length with the increase of Zn doping improves interlayer coupling and hence the three-dimensional conductivity in the unit cell. The role of charge carriers in CuO 2 planes of Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4-y Zn y O 12-δ in bringing about superconductivity has also been explained. PACS: 74.70.-b Superconducting materials other than cuprates; 74.62.Bf Effects of material synthesis, crystal structure, and chemical composition; 74.25.Uv Vortex phases (includes vortex lattices, vortex liquids, and vortex glasses). Keywords: Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4-y Zn y O 12-δ superconductors, antiferromagnetism, charge stripes, charge carriers.