Figure 1

Schematic diagrams of electronic transport for a ultraclean sample (narrow Landau levels and weak overlapping). (a) In the lower part, no MW field is present. (b) The orbits move backwards during the jump, and the scattering ends around the central part of a LL (grey stripes); then, we have full contribution to the current. (c) The scattering jump ends in between LL (white stripes), giving rise to a negligible contribution to the current because the low density of final Landau states. (d) We depict a ZRS situation. Dotted line represents the Fermi level before the scattering jump; white and black circles represent empty and occupied orbits after the jump, respectively.