Electronic conductance of one-dimensional chains with phonon dephasing disorder

In this paper we analyse how electron transport through a one-dimensional chain is modified by the presence of phonon dephasing mechanisms active in a limited strand of the chain. The treatment is based on the nonequilibrium Keldysh Green's function and the self-consistent first Born approximation, with a tight-binding description of the electronic states. A most remarkable feature of the calculated conductance curves is the occurrence of an exponential decrease for small lengths, followed by a slow asymptotic decrease inversely proportional to the strand length. The origin of such a different short-range and long-range behaviour of the conductance, and other observed scaling features, are interpreted with some intuitive understanding of the dephasing mechanisms.