Reentrant quantum Hall effect and anisotropic transport in a bilayer system at high filling factors

We report on the measurements of the quantum Hall effect states in double quantum well structures at the filling factors nu=4N+1 and nu=4N+3, where N is the Landau index number, in the presence of the in-plane magnetic field. The quantum Hall states at these filling factors vanish and reappear several times and exhibit anisotropy. Repeated reentrance of the transport gap occurs due to the periodic vanishing of the tunneling amplitude in the presence of the in-plane field. Anisotropy demonstrates the existence of the stripes in the ground states.