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Nonohmic conductivity as a probe of crossover from diffusion to hopping in two dimensions

G. M. Minkov·A. A. Sherstobitov·O. E. Rut·A. V. Germanenko
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Abstract

We show that the study of conductivity nonlinearity gives a possibility to determine the condition when the diffusion conductivity changes to the hopping one with increasing disorder. It is experimentally shown that the conductivity of single quantum well GaAs/InGaAs/GaAs heterostructures behaves like diffusive one down to value of order $10^{-2}e^2/h$.

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G. M. Minkov, A. A. Sherstobitov, O. E. Rut, A. V. Germanenko. 2003-12-04. Nonohmic conductivity as a probe of crossover from diffusion to hopping in two dimensions. https://doi.org/10.1016/j.physe.2004.05.006

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