Tunable ballistic rectification in a density-modulated two-dimensional-system

We demonstrate tunable rectification in a density-modulated two-dimensional electron gas (2DEG). The density modulation is induced by two surface gates, running in parallel along a narrow strip of 2DEG. A transverse voltage in the direction of the density-gradient is observed, i.e. perpendicular to the applied source-drain voltage. The transverse voltage depends on the sign and magnitude of the density gradient. The polarity of the transverse voltage is independent of the polarity of the source-drain voltage demonstrating rectification in the device. The experimental results are discussed in the framework of a classical, single particle billiard model.