ELECTRON BAND-STRUCTURE IN A 2-DIMENSIONAL PERIODIC MAGNETIC-FIELD

In this paper we study the energy spectrum of a two-dimensional electr on gas (2DEG) in a two-dimensional periodic magnetic field. Both a squ are magnetic lattice and a triangular one are considered. We consider the general case where the magnetic field in a cell can be of any shap e. A general feature of the band structure is bandwidth oscillation as a function of the Landau index. A triangular magnetic lattice on a 2D EG can be realized by the vortex lattice of a superconductor film coat ed on top of a heterojunction. Our calculation indicates a way of rela ting the energy spectrum of the 2DEG to the vortex structure. We have also derived conditions under which the effects of a weak magnetic mod ulation, periodic or not, may be reproduced by an electric potential m odulation, and vice versa.