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In this work, the edge physics of an Aharonov-Bohm interferometer (ABI) defined on a two dimensional electron gas, subject to strong perpendicular magnetic field B, is investigated. We solve the three dimensional Poisson equation using numerical techniques starting from the crystal growth parameters and surface image of the sample. The potential profiles of etched and gate defined geometries are compared and it is found that the etching yields a steeper landscape. The spatial distribution of the incompressible strips is investigated as a function of the gate voltage and applied magnetic field, where the imposed current is confined to. AB interference is investigated due to scattering processes between two incompressible "edge-states".

We report on our theoretical investigation of the effects of the confining potential profile and sample size on the electron velocity distribution in (narrow) quantum Hall systems. The electrostatic properties of the electron system are obtained by the Thomas-Fermi-Poisson nonlinear screening theory. The electron velocity distribution as a function of the lateral coordinate is obtained from the slope of the screened potential at the Fermi level and within the incompressible strips. We compare our findings with the recent experiments. © 2007 The American Physical Society

The effect of the external electric field on the ground state binding energy and self‐polarization of a hydrogenic donor impurity in quantum wells (QWs) made of different materials is calculated within the effective mass approximation using a variational scheme. The variations of binding energy and self‐polarization depending on well width, electric field, and impurity position have been studied in detail. For each QW made of different materials, it has been observed that the binding energy decreases with the increase of the electric field, whereas the self‐polarization increases. Also, it has been observed that InP/In1−x Ga x P has higher binding energy values among the structures discussed. It is seen that material selection has a noticeable effect on self‐polarization and binding energy in QW‐based structures.