Fractional charge in transport through a 1D correlated insulator of finite length

Transport between two Fermi liquid reservoirs through a one channel wire of length L is examined when the 1D electron system has an energy gap 2M >> upsilon(c)/L (upsilon(c) is the charge velocity in the wire). In the spinless case transformation of reservoir electrons into solitons of fractional charge entails a crossover from a Fermi liquid regime of integer charge transfer below the crossover energy T-x << T-L to an insulating regime of the fractional charge transfer in the current vs voltage, conductance vs temperature, and the shot noise. Similar behavior is predicted for a spin Mott insulator of filling factor nu = n/(2m') (n, m' are positive integers).