Dependence of electronic rectification in carbon nanocone devices upon electrode materials

Very recently, we found that single-walled carbon nanocones (SWCNCs) of tens of atoms can serve as rectifiers if Au electrodes are applied (Ming et al 2012 Appl. Phys. Lett. 100 063119). In this paper, the dependence of rectification effects on different electrode materials (Au, Cu, Ag, Li, Be, Pd and Pt) is systematically investigated by density functional theory and non-equilibrium Green's function, showing that materials with lower energy bonded with the SWCNC possess better rectification effects. The rectification mechanism is revealed, including the fact that the contact distance between the tip of the SWCNC and the electrode is also an important factor for rectification effects.