Slow relaxation of conductance of amorphous hopping insulators
نویسنده
چکیده
We discuss memory effects in the conductance of hopping insulators due to slow rearrangements of structural defects leading to the formation of polarons close to the electron hopping states. An abrupt change in the gate voltage and corresponding shift of the chemical potential change the populations of the hopping sites, which then slowly relax due to rearrangements of structural defects reducing the density of states. As a result, the density of the hopping states becomes time dependent on a scale relevant to the rearrangement of the structural defects, leading to excess time-dependent conductivity.
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