Some aspects of glass-ceramic superconductors

Abstract

In this review article we have discussed, in brief, the general procedure for making glass-ceramic superconductors and some of their physical properties. All these glasses which become superconductors after properly annealing at higher temperatures are, in general, transition metal oxides (TMO) with copper ions. So the usual theoretical models of polaronic hopping conduction mechanisms are valid for explaining the semiconducting behaviour of these oxide glasses. Some of the transport properties of the glass-ceramic (GC) phases, viscosity of the glassy state, wire making feasibility etc have also been discussed in short.

Critical aspects on preparation of Bi-2223 glassy precursor by melt-process

“…The resulting precursor should be completely amorphous, with a chemical composition equal to the nominal one and free of impurities. In order to maximize applications of materials prepared via the glass-ceramic route there was substantial attention during the 1990's focused on seeking optimized initial compositions, glass forming ability, processing conditions and material properties on the BSCCO system [61,62]. However, the main investigations were more focused on the verification of the amorphous state than on the control of the chemical composition.…”