Physical mechanisms of nonlinear conductivity: A model analysis

Abstract

Nonlinear effects are omnipresent in thin films of ion conducting materials showing up as a significant increase of the conductivity. For a disordered hopping model general physical mechanisms are identified giving rise to the occurrence of positive or negative nonlinear effects, respectively. Analytical results are obtained in the limit of high but finite dimensions. They are compared with the numerical results for 3D up to 6D systems. A very good agreement can be found, in particular for higher dimensions. The results can also be used to rationalize previous numerical simulations. The implications for the interpretation of nonlinear conductivity experiments on inorganic ion conductors are discussed.

Nonlinear ion transport in the supercooled ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide: Frequency dependence of third-order and fifth-order conductivity coefficients

“…[14][15][16][17][18] Other models predict positive third-order a) Email: laxminar@chemie.uni-marburg.de dc conductivity coefficients, which are, however, much smaller than those found in experiments. 19,20 The frequency dependence of the third-order conductivity spectra of solid ion conductors differs clearly from the universal dynamic response observed in the linear spectra. At low frequencies, a dc plateau regime is detectable in the third-order spectra.…”

“…It has been found that several models which provide a good description of linear conductivity spectra fail to properly reproduce nonlinear conductivity spectra. For instance, some models predict negative thirdorder dc conductivity coefficients, 19 whereas the third-order dc conductivity coefficients observed in experiment were always positive. [14][15][16][17][18] Other models predict positive third-order a) Email: laxminar@chemie.uni-marburg.de dc conductivity coefficients, which are, however, much smaller than those found in experiments.…”

Dynamics of silver ions in AgI doped Ag2O–SeO2–MoO3 mixed former glasses

“…13 Ac conductivity spectroscopy has been widely used to study the charge carrier dynamics in different time and length scales. [14][15][16] It is observed that at low frequency or longer time scale the ac conductivity is almost independent of frequency and the ion transport is characterized by the long range diffusive motion of mobile ions. At higher frequency or shorter time scale dispersion is set up and the conductivity increases with the increase in frequency as a result of correlated forward-backward jumps of mobile ions and the ion transport is characterized by the sub-diffusive motion of mobile ions.…”

Hopping-Transport Mechanism for Reconfigurable Logic in Disordered Dopant Networks

“…Interestingly, there is no obvious correlation between a particular gate and its voltage and current distribution, as shown by the completely different voltage and current distributions for another device in Fig. 9 in Appendix F. Also, for the hopping dynamics in other disordered systems, it has been found that the total current in the nonlinear regime does not need to be related to some obvious pattern of the current distribution [18].…”