Probing the potential landscape inside a two-dimensional electron-gas

TL;DR

This study uses electron-beam diffraction to directly observe and manipulate scattering potentials caused by local density fluctuations in a 2D electron gas within GaAs heterostructures, revealing insights into the internal potential landscape.

Contribution

It provides the first direct visualization of scattering potentials in a 2D electron gas and demonstrates external control over these potentials through illumination and temperature adjustments.

Findings

Direct observation of scattering potentials via electron diffraction.

Manipulation of potential landscape through external stimuli.

Identification of donor-induced density fluctuations as scatterers.

Abstract

We report direct observations of the scattering potentials in a two-dimensional electron-gas using electron-beam diffaction-experiments. The diffracting objects are local density-fluctuations caused by the spatial and charge-state distribution of the donors in the GaAs-(Al,Ga)As heterostructures. The scatterers can be manipulated externally by sample illumination, or by cooling the sample down under depleted conditions.