Volume 42, Issue 1, 2021
Saturday, July 10, 2021
This article reports on the effects of tungsten, W substitution at the Tl site of (Tl1-xWx)(BaSr)Ca2CuO7 superconductor. The samples were prepared through the solid-state reaction method. The resistance versus temperature curves were determined by using the four-point probe method. The AC susceptibility was measured and intergrain current density at the peak temperature of the imaginary part of the susceptibility χ”, Jc(Tp) was determined. The sample without W substitution showed the highest onset transition temperature, Tc-onset at 108 K and zero-resistance temperature, Tc-zero at 86 K. The susceptibility transition temperature, Tcχ’ decreased with W substitution. The peak temperature, Tp of imaginary part of the susceptibility shifted to lower temperatures and broadened as W content was increased. This indicated that W weakened the flux pinning and intergrain coupling. Jc(Tp) for x = 0-0.4 were between 17 and 20 A cm-2.