For the first time, University of Wisconsin–Madison researchers directly measured the fluid-like flow of electrons in Graphene at nanometer resolution. They published their results in Journal Science.
Graphene’s atom-thick sheet of carbon arranged in a honeycomb pattern is a nearly pure electrical conductor, so it’s ideal for studying electron flow with very low resistance. The researchers intentionally added impurities at known distances and found that electron flow changes from gas-like to fluid-like as the temperature rises. The results enable applications in new, low-resistance materials, where electrical transport would be more efficient.
Using a technique known as scanning tunneling potentiometry (STP) and the 2D material graphene, the researchers introduced obstacles spaced at controlled distances, then applied a current across the Graphene. They measured the voltage with nanometer resolution at all points on the Graphene, producing a 2D map of the electron flow pattern. The drop in voltage through the channel was much lower at a higher temp (77 kelvins) vs. a lower temp (4 K), indicating more electrons were passing through. The electrons flowed more freely and fluid-like.
