We have developed a practical approach for the inclusion of magnetic fields in the nonequilibrium Green's function method and we have formulated a general scheme for transport calculations in a multiterminal device with magnetic field. Formulas for the self-energy terms in the presence of magnetic fields have been derived and disorder effects in the potential have been introduced through a model accounting for scattering by impurities. To demonstrate the validity of the model, we have applied it to the quantum Hall effect (QHE), for which a wealth of experimental results and information is readily available. Calculations for a simple structure at zero temperature were first carried out to verify the properties of the solutions over a wide range of conditions. The calculated Green's function results provide the carrier density distribution in the structure, and in order to analyze the QHE results, the resistances Rxx and Rxy are obtained using Büttiker's approach. Our results for the integer QHE show a pattern that clearly resembles the edge state picture of transport. To further validate the theoretical model, comparisons have been conducted with experimental results for a realistic quantum Hall device at finite temperature, obtaining good agreement.
|Number of pages||9|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - May 1 2003|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics