Conductance scaling of molecular wires in parallel

Charge transport across a metal-molecule-metal junction consisting of pi-conjugated molecular wires in a densely packed monolayer is studied as a function of junction area. The current-voltage characteristics, measured using a crossed-wire junction at different contact forces, scale onto a single curve. The integer scaling factors, ranging from 1 to 1119, are dictated by the number of molecules contacted in each measurement. These results demonstrate that the electronic conductance of an ensemble of molecules scales directly with the number of molecules in the junction. Our results, which also imply that molecular wires connected in parallel are not strongly coupled along their molecular backbone, should aid in the future development of molecular electronic devices.