Electrons flowing like liquid in graphene start a new wave of physics

said braka 2:43 AM
Graphene is many times more conductive than copper

thanks, in part, to its two-dimensional structure. In most metals, conductivity is limited by crystal imperfections which cause electrons to frequently scatter like billiard balls when they move through the material.
Now, observations in experiments at the National Graphene Institute have provided essential understanding as to the peculiar behaviour of electron flows in , which need to be considered in the design of future Nano-electronic circuits.
In some high-quality materials, like graphene, electrons can travel micron distances without scattering, improving the conductivity by orders of magnitude. This so-called ballistic regime, imposes the maximum possible conductance for any normal metal, which is defined by the Landauer-Buttiker formalism.
Appearing today in Nature Physics, researchers at The University of Manchester, in collaboration with theoretical physicists led by Professor Marco Polini and Professor Leonid Levitov, show that Landauer's fundamental limit can be breached in graphene. Even more fascinating is the mechanism responsible for this.
Last year, a new field in solid-state physics termed 'electron hydrodynamics' generated huge scientific interest. Three different experiments, including one performed by The University of Manchester, demonstrated that at certain temperatures, electrons collide with each other so frequently they start to flow collectively like a .
The new research demonstrates that this viscous fluid is even more conductive than ballistic electrons. The result is rather counter-intuitive, since typically scattering events act to lower the conductivity of a material, because they inhibit movement within the crystal. However, when electrons collide with each other, they start working together and ease current flow.


Read more at: https://phys.org/news/2017-08-electrons-liquid-graphene-physics.html#jCp