Superballistic flow of viscous electron fluid through graphene constrictions

Understand

Electron-electron (e-e) collisions can impact transport in a variety of surprising and sometimes counterintuitive ways.

• Despite strong interest, experiments on the subject proved challenging because of the simultaneous presence of different scattering mechanisms that suppress or obscure consequences of e-e scattering.
• Only recently, sufficiently clean electron systems with transport dominated by e-e collisions have become available, showing behavior characteristic of highly viscous fluids.
• Here we study electron transport through graphene constrictions and show that their conductance below 150 K increases with increasing temperature, in stark contrast to the metallic character of doped graphene.