Comprehensive studies of dielectric behavior, resistive switching, and a.c. conduction in zinc-containing quaternary glasses of Se-Te-Sn

The dielectric behavior, thermally activated a.c. conduction and resistive switching form the basis for revealing new information about the conduction mechanics of glassy chalcogenide materials. Zinc has been chosen as a modifier to control different electrical properties in a parent ternary glass Se ₇₈Te ₂₀Sn ₂ of Se-Te-Sn system in the present work keeping in mind the exceptional physical properties of zinc chalcogenides. The detailed analysis indicates that dielectric constant (ε′), dielectric loss (ε″), and a.c. conductivity ( σ_ac) is changed appreciably with varying concentrations of zinc atoms in the parent glass. The a.c. conduction follows the correlated barrier hopping (CBH) with bi-polaron hopping as the leading conduction mechanism. We have also determined the density of localized states by using the CBH model. Further, the resistive switching is modified significantly after zinc incorporation. The results have been explained using the chemically ordered network (CON) model and heavy cross-linking of glass-matrix due to isomers of Se _yZn _y nanoclusters.