If you set it up right, electrons in graphene stop acting like bouncy particles and start flowing together like thick honey.
arXiv · March 13, 2026 · 2603.11175
Why it matters
Usually, electrons in a wire act like a gas, scattering off impurities. This study imaged electrons entering a 'hydrodynamic' state where they flow collectively as a viscous liquid, potentially allowing for much smaller and more efficient electronic devices.
From the abstract
Hydrodynamic electron transport arises when carrier kinetics are dominated by interelectron collisions rather than the relaxation of momentum out of the electron system. In recent years, signatures of electron hydrodynamics have been reported in graphene devices owing to the low disorder and weak electron-phonon coupling. However, these experiments have been performed in regimes where the carrier mass is light, and the electron-electron collision length--though smaller than corresponding lengths