Distinguishing thermal from non-thermal ("hot") in illuminated molecular junctions

The search for the signature of non-thermal (so-called "hot") electrons in illuminated plasmonic nanostructures requires detailed understanding of the non-equilibrium electron distribution under illumination, as well as a careful design of the experimental system employed to distinguish non-thermal electrons from thermal ones. Here, we provide a theory for using plasmonic molecular junctions to achieve this goal. We show how non-thermal electrons can be measured directly and separately from the unavoidable thermo-electric response, and discuss the relevance of our theory to recent experiments.