ANALYSIS OF CONTACT AND CHARGING EFFECTS ON NONEQUILIBRIUM ELECTRONIC TRANSPORT IN NANOSTRUCTURES

摘要

In this study, we adopted extended Huckel theory (EHT) combined with nonequilibrium Green's function (NEGF) to deal with the transport problem of single 4, 4'-bipyridine molecule sandwiched between two gold electrodes. The dependence of the transport characteristics on gold-nitrogen bond length and torsion angle is investigated. Furthermore, the influence of the charging effect on the transport characteristics is emphasized. We note that the orientation of the molecule plays a crucial role in electronic conduction and the current is also strongly dependent on distance between the molecule and electrodes. The results we obtained are in general agreement with previous works and are discussed.