Interaction of surface acoustic waves with a two-dimensional electron system in a LiNbO3-GaAs/AlGaAs sandwich structure

We describe a simple, contactless method to study the interaction of surface acoustic waves (SAW) with a two-dimensional electron system (2DES) in GaAs/AlGaAs heterostructures at low temperatures and in high magnetic fields. The heterostructure is part of a sandwich structure on a Y-cut Z-propagating LiNbO3-SAW-delay line. The interaction of the SAW with the 2DES leads to quantum oscillations of the SAW amplitude as a function of the applied magnetic field which can be used to characterize the sample and to investigate the transport properties of the 2DES.