First-principles approach to the electron transport and applications for devices based on carbon nanotubes and ultrathin oxides

We use a first-principles computational scheme to study the transport properties of devices based on telescoping carbon nanotubes. The transmission function is calculated through the matrix Green's function method using a Gaussian basis set. Varying the overlap region of the two nanotubes, we compare the effect of interwall interactions on the transport characteristics with that obtained from a simple tight-binding model. The leakage current through ultrathin gate oxides is also studied for various Si/SiO2 interface models, which are manipulated by varying oxide thickness and crystal phase.