Concentration-dependent acoustic and electrical properties of highly conducting Bi3.5Pb0.5Sr3Ca3Cu4Oz + xAg2O-type glassy precursors for high-T c superconductors

摘要: Abstract We report the concentration-dependent electrical conductivity and acoustic parameters of (Bi-Pb)4Sr3Ca3Cu4Oz + xAg2O (x = 0-10 wt%)-type glassy precursors for high T c superconductors. Unlike (Bi, Pb)4Sr3Ca3Cu4OZ, or many other transition-metal oxide glasses, these Ag-containing glasses are highly conducting. small-polaron hopping mechanism conduction is found not to be applicable which might due a partial contribution Ag ions conductivity. The velocities sound, elastic constants, microhardness, impedance Debye temperatures decrease monotonically, as does density, with increasing concentration. On hand, thermal expansion coefficient, internal friction Poisson's ratio increase content Ag2O. corresponding derived quantities indicate softening glass structure a...