We study the effect of magnetic field on the properties of a high mobility
gated two-dimensional electron gas in a field effect transistor with the Hall
bar geometry. When approaching the current saturation when the drain side of
the channel becomes strongly depleted, we see a number of unusual effects
related to the magnetic field induced re-distribution of the electron density
in the conducting channel. The experimental results obtained in the non-linear
regime have been interpreted based on the results obtained in the linear regime
by a simple theoretical model, which describes quite well our observations.Comment: 6 pages, 8 figure