Classical transport of electrons through magnetic barriers

We investigate the magnetoresistance of a two-dimensional electron gas (2DEG) in the presence of wide (width of order $\mu$m) magnetic barriers. A Poisson-like equation is solved numerically from which we obtain the 2D electrostatic potential, electric field, and current distribution in the 2DEG. We found that most of the electrons are injected at the edge of the magnetic barrier and most of the potential drop takes place in the barrier region. Major features of a recent magnetoresistance experiment by Leadbeater et al. [Phys. Rev. B 52, R8629 (1995)] on single and double faceted structures can be explained by our classical approach. The positive background magnetoresistance and the nonlocal Hall effect are reproduced. These results allow one to disentangle classical and quantum features of the experimental results.