Gap size dependent transition from direct tunneling to field emission in single molecule junctions

摘要

I/V characteristics recorded in mechanically controllable break junctions revealed that field emission transport is enhanced in single molecule junctions as the gap size between two nano-electrodes is reduced. This observation indicates that Fowler-Nordheim tunneling occurs not only for intermolecular but also for intramolecular electron transport driven by a reduced energy barrier at short tunneling distances.