Variable-range hopping

Variable-range hopping is a model used to describe carrier transport in a disordered semiconductor or in amorphous solid by hopping in an extended temperature range. It has a characteristic temperature dependence of

${\displaystyle \sigma =\sigma _{0}e^{-(T_{0}/T)^{\beta }}}$

where ${\displaystyle \sigma }$ is the conductivity and ${\displaystyle \beta }$ is a parameter dependent on the model under consideration.