Magnetoresistance oscillations due to internal Landau band structure of a two-dimensional electron system in a periodic magnetic field

We report alternative types of magnetoresistance oscillations in high mobility two-dimensional electron systems subjected to large amplitude one-dimensional periodic magnetic modulations, of period 500 nm to 1 Am. We observe Shubnikov-de Haas oscillations that are strongly modified in amplitude and phase, Hall resistance oscillations. and aperiodic magnetoresistance oscillations. These effects are shown to arise from the internal structure of overlapping Landau bands and are well accounted for by perturbation calculations.