Mapping the Conductance of Electronically Decoupled Graphene Nanoribbons

With the advent of atomically precise synthesis and consequent precise tailoring of their electronic properties, graphene nanoribbons (GNRs) have emerged as promising building blocks for nanoelectronics. Before being applied as such, it is imperative that their charge transport properties are investigated. Recently, formation of a molecular junction through the controlled attachment of nanoribbons to the probe of a scanning tunneling microscope (STM) and subsequent lifting allowed for the first conductance measurements. Drawbacks are the perturbation of the intrinsic electronic properties through interaction with the metal surface, as well as the risk of current-induced defect formation which largely restricts the measurements to low bias voltages. Here, we show that resonant transport – essential for device applications – can be measured by lifting electronically decoupled GNRs from an ultrathin layer of NaCl. By varying the applied voltage and tip–sample distance, we can probe resonant transport through...