Abstract
Using analytical arguments and computer simulations, we show that the dependence of the hopping carrier mobility on the electric field in a system of random sites is determined by the localization length , and not by the concentration of sites . This result is in drastic contrast to what is usually assumed in the literature for a theoretical description of experimental data and for device modeling, where is considered as the decisive length scale for . We show that although the limiting value is determined by the ratio , the dependence is sensitive to the magnitude of , and not to . Furthermore, our numerical and analytical results prove that the effective temperature responsible for the combined effect of the electric field and the real temperature on the hopping transport via spatially random sites can contain the electric field only in the combination .
- Received 12 December 2016
- Revised 26 June 2017
DOI:https://doi.org/10.1103/PhysRevB.96.035204
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