EXPERIMENTAL CHARACTERIZATION OF ELECTRON TRAJECTORIES IN ANTIDOT LATTICES

The magnetic-field-dependent conductivity of a square antidot lattice is calculated from the experimentally determined magnetoresistance and Hall resistance. Close to the commensurability conditions where the magnetoresistance always displays pronounced maxima we find a crossover from minima to maxima in the conductivity as a function of antidot size. We interpret this behavior in terms of different classes of electron trajectories whose relative importance depends on the size of the antidots with respect to the lattice period.