The effect of Sn substitution in the (Hg1-xSnx)Ba(2)Ca(2)Cu(3)Oy superconducting system

We studied the effect of Sn substitution in a new mercury-based superconductor with nominal composition (Hg1-xSnx)Ba2Ca2Cu3Oy (0 less than or equal to x less than or equal to 0.5). At this stage of investigation the material is multiphasic with dominating superconducting phases up to x = 0.3. It was established that Sn stimulates the formation of the Hg-1212 phase and enhances the diamagnetic volume fraction but also the weak-link behaviour. Together with the SEM-EDS analysis, the shift of some of the XRD peaks, as well as the gradual decrease of T-c with the dopant content x, suggests that the substitution is effective and some of the Sn is incorporated into the structure of the superconducting phases.