Effects of tip separation and orientation on negative differential resistance in boron-doped carbon-nanotube-based molecular junctions

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.