Electron Hydrodynamics

2021, Jun 04 Georgios Varnavides One min read

Schematic of the emergence of steady-state vortices in anisotropic hydrodynamic flow — Difference in steady-state streamplot between isotropic and square-symmetry viscosity tensors in a corbino disk geometry, highlighting the emergence of steady-state vortices

In most conductors at room-temperature, electron collisions are akin to billiard balls, resulting in the macroscopic observation of diffusive flow (Ohm’s “law”). Recently, spatially-resolved transport measurements have revealed electrons in strongly-interacting materials can behave akin to classical fluids, confirming theoretical predictions over fifty years old.

I study these “hydrodynamic” electron flows across various length scales, from their microscopic origins, to mesoscopic finite-size effects, and to their macroscopic observables. Recently, I was part of a team which imaged these flows in a 3D conductor for the first time, corroborating a newly-proposed electron interaction mechanism mediated by lattice vibrations.

Currently, as a postdoctoral Miller research fellow, I’m developing computational imaging techniques to correlate such non-uniform current densities with the underlying structure, opening the door to investigating the role of structure and defects in designing near-dissipation-less electronics and inviting questions like “does current flow around defects in materials similar to how rivers flow past pebbles? If so, can we engineer them to minimize thermal dissipation?”