Abstract
Green’s Function is used to calculate the conductance in narrow wires which include several types of scatters. The research subjects are narrow wires, so the transport properties of the electrons belong to quantum transport, which is totally different from classic transport. This study discusses about the narrow wires that include: (1) a single scattering center, (2) rectangular potential barrier and (3) random distributed scattering centers. Both repulsive and attractive potentials are considered in each case. The delta function potentials are used for the discrete scattering centers. First, we use the Schrodinger equation to calculate the eigenvalues and eigenfunctions of the confined transverse modes of the narrow wires. Then, we use them to calculate the Green’s function in order to calculate the transmission probability. After that, we use the Landauer formula to calculate conductance. The results display the physical phenomena of quantum transport. The stepwise increases of quantum conductance are found for these wires. For a single attractive defect in the wire, there is a dip in the conductance caused by the existence of the quasi-donor level. For the rectangular barrier in the wire, there are resonances in the conductance which are similar to those of the potential barrier and well in quantum mechanics. For the random positive defects in the wire, there appears fluctuation in the conductance. This phenomenon helps us to understand the quantum interference effects. By changing part of the defects from repulsive to negative, the conductance is modified. There are some dips in the conductance due to the quasi-donor levels. The results are consistent with the work of Bagwell and Kumar [1, 2], who use the Scattering-Matrix to calculate conductance。