Abstract
We present experimental images and computer simulations of electron and conduction-band-hole trajectories transmitted between two series constrictions in a two-dimensional electron gas formed at a GaAs/AlGaAs heterojunction. The electric perturbation of a scanning charged probe modified the trajectories to generate the experimental images. In a weak magnetic field, the images revealed cyclotron orbits allowing a measurement of electron and conduction-band-hole energies. Using the same technique, a scattering site caused a 26° change in the trajectories. Computer simulations with localized charge fluctuations in the donor layer, which locally distort the conduction band by of the Fermi energy, reproduced structures seen in the experimental images and features in a related magnetic steering experiment. Conduction-band-holes are holelike quasiparticles in the conduction band with an energy less than the Fermi energy, being equivalent to unoccupied electron states.
- Received 23 September 1999
DOI:https://doi.org/10.1103/PhysRevB.62.5174
©2000 American Physical Society