By applying non-equilibrium Green's function in combination with density functional theory,we investigated the electronic transport properties of capped-carbon-nanotube-based molecular junctions with multiple N and B dopants.The results show that the electronic transport properties are strongly dependent on the numbers and positions of N and B dopants.Best rectifying behavior is observed in the case with one N and one B dopants,and it is deteriorated strongly with the increasing dopants.The rectifying direction is even reversed with the change of doping positions.Moreover,obvious negative differential resistance behavior at very low bias is observed in some doping cases.
We investigate using the Landauer formalism,which combines both the non-equilibrium Green's function and density functional theory,the effects of separation and orientation between two electrodes of boron-doped capped-carbon-nanotube-based molecular junctions on negative differential resistance.The results show that this negative differential resistance behavior is strongly dependent on the separation and orientation between the two electrodes.A gap width of 0.35 nm and maximal symmetry achieves the best negative differential resistance behavior.
