Hopping Conductivity in One Dimension

An asymptotic upper bound at low temperatures σ∝e^-TT₀ is established to the electrical conductivity of the Mott hopping model in one dimension. This removes the logical basis for arguing in favor of hopping conductivity in one dimension, $d=1$, using the asymptotic form σ∝exp[-(T₀T)1/(1+d)] as recently proposed for certain highly inhomogeneous solids.