Electron transport in multiterminal molecular devices: A density functional theory study

The electron transport properties of a four-terminal molecular device are computed within the framework of density functional theory and nonequilibrium Keldysh theory. The additional two terminals lead to new properties, including a pronounced negative differential resistance not present in a two-terminal setup, and a pseudogating effect. In general, quantum interference between the four terminals and the central molecule leads to a complex nonlinear behavior of the current, which depends on the alignment of individual molecular states under bias and their coupling to the leads.