TRANSPORT IN A BILAYER SYSTEM AT HIGH LANDAU FILLING FACTOR

We have studied Shubnikov de Haas oscillations and the quantum Hall effect in GaAs-double well structures in tilted magnetic fields. We found strong magnetoresistance oscillations as a function of an in-plane magnetic field B(parallel to) at nu = 4N + 3 and nu = 4N + 1 filling factors. At low perpendicular magnetic field B(perpendicular to), the amplitude of the conventional Shubnikov-de Haas (SdH) oscillations also exhibits B(parallel to)-periodic dependence at fixed values of B(perpendicular to). We interpret the observed oscillations as a manifestation of the interference between cyclotron orbits in different quantum wells.