Description
Electronic Transport at the Nanoscale:
Due to the downscaling of electrical components by several orders of magnitude during the past decades they feature now lateral structure sizes of only tens of nanometers. The resistance of macroscopic conductors is described by Ohm’s law, assuming diffusive charge transport carried by the conduction electrons. Surprising enough, for describing their transport properties the laws of macroscopic solid state physics can be applied with minor corrections arising from the quantum nature of transport. In this mesoscopic regime quantum interference effects come into play. Upon further miniaturization also this approach breaks down. When approaching the structure sizes of only a few nanometers, the electrical current obeys different laws than in macroscopic conductors. At the nanoscale electrons move ballistically and transport needs to be described using a quantum mechanical scattering approach. We will review the concepts used to describe mesoscopic and quantum conductors and give examples for typical structures and devices.