  Contrary to common belief, the current emitted by a contact embedded in a
two-dimensional electron gas (2DEG) is quantized in the presence of electric
and magnetic fields. This observation suggests a simple, clearly defined model
for the quantum current through a Hall device that does not invoke disorder or
interactions as the cause of the integer quantum Hall effect (QHE), but is
based on a proper quantization of the classical electron drift motion. The
theory yields a quantitative description of the breakdown of the QHE at high
current densities that is in agreement with experimental data. Furthermore,
several of its key points are in line with recent findings of experiments that
address the dependency of the QHE on the 2DEG bias voltage, results that are
not easily explained within the framework of conventional QHE models.
