Jump relaxation in solid ionic conductors
Correlated forward-backward hopping sequences of individual mobile charged defects are the elementary processes of jump relaxation in solid ionic conductors. The phenomenon is due to the repulsive interaction between defects. The microscopic dynamics of the relaxation is described in a simple model which yields in particular the frequency spectrum of the hopping motion. With the help of this function, it is possible to explain the experimental manifestations of the “universal dynamic response”, including the well-known arcs in the complex planes of conductivity and permittivity, the power-law frequency dependence of the ionic conductivity, as well as the non-BPP-type behaviour of spin-lattice relaxation times and the broad components of quasielastic neutron scattering spectra.