ELECTRONIC BAND-STRUCTURE IN A PERIODIC MAGNETIC-FIELD

We analyze the energy band structure of a two-dimensional electron gas in a periodic magnetic field of a longitudinal antiferromagnet by con sidering a simple exactly solvable model. Two types of states appear: with a finite and infinitesimal longitudinal mobility. Both types of s tates are present at a generic Fermi surface. The system exhibits a tr ansition to an insulating regime with respect to the longitudinal curr ent, if the electron density is sufficiently low.