Physics

Electron scattering

Electron

Nanotechnology

Perturbation (astronomy)

Optics

Atomic physics

Electron transport chain

Chemistry

Scattering

Materials science

Scanning electron microscope

Condensed matter physics

Graphene

Molecular physics

Quantum mechanics

Observable

Biochemistry

Physical review. B./Physical review. B

We measure transport through a Ga[Al]As heterostructure at temperatures between $32\phantom{\rule{3.33333pt}{0ex}}\mathrm{mK}$ and $30\phantom{\rule{3.33333pt}{0ex}}\mathrm{K}$. Increasing the temperature enhances the electron-electron scattering rate and viscous effects in the two-dimensional electron gas arise. To probe this regime we measure so-called vicinity voltages and use a voltage-biased scanning tip to induce a movable local perturbation. We find that the scanning gate images differentiate reliably between the different regimes of electron transport. Our data are in good agreement with recent theories for interacting electron liquids in the ballistic and viscous regimes stimulated by measurements in graphene. However, the range of temperatures and densities where viscous effects are observable in Ga[Al]As are very distinct from the graphene material system.

Scanning gate microscopy in a viscous electron fluid