Electronic conductance in open quantum dots

We simulate electron transport through a model open quantum dot device in a two-dimensional electron gas. The dot is defined by a circular region enclosed by two metallic gates, with two small openings at its ends. We show that the differential conductance has different behaviours as a function of the magnetic field: for low fields irregular oscillations are present, while a typical Aharonov - Bohm pattern appears in the integer quantum Hall regime. Our numerical results are interpreted by means of the theoretical imaging of current distribution and local density-of-states, obtained by the Keldysh Green's function formalism.