Altering regularities on resistances of doped Au–alkanedithiol–Au junctions

Abstract

The electronic transport properties of alkanedithiol molecular junctions doped by boron (B) or phosphorus (P) on different sites are investigated by using the non-equilibrium Green’s function method combined with the density functional theory. Results show that B or P doping can decrease the resistances of alkanedithiol molecular junctions obviously and the direct-current conductance becomes stronger gradually when doped sites vary from side to center. Namely, the B or P doped effects are not uniform which are sensitive to its doped sites. Interestingly, significant negative differential resistance behaviors are only found in B-doped molecular junctions and peak-to-valley ratios are also sensitive to the B doped sites.