Single-electron transistor probes two-dimensional electron system in the quantum Hall regime

Abstract

Here we summarize briefly our recent experimental results on probing a two-dimensional electron system (2DES) in high magnetic fields by using a single-electron transistor (SET) made of aluminum which was deposited on top of a GaAs/AlGaAs heterostructure containing the 2DES close to the surface. This arrangement allows to measure the chemical potential variations of the 2DES with magnetic field and to probe the electrostatic potential profile at the 2DES's edge which we defined by electrostatic depletion by a gate electrode close to the SET. Compressible and incompressible strips are detected in the depletion region of the 2DES in the integer quantum Hall regime on a width of less than 1 μm.