Spatial distribution of nonequilibrium current in a magnetic field

The spatial distribution of the nonequilibrium current and charge distribut ions in a series of two point contacts are studied in the presence of a mag netic field making use of a recursive Green function method based on the Ke ldysh formalism. Numerical results show that the structure of Vortices appe aring in between two barriers depends strongly on the applied bias voltage. The chemical potential dependence of the total current is also investigate d.