Magnetotransport properties of arrays of cross-shaped antidots

In magnetotransport measurements on arrays of cross-shaped antidots, we obs erve pronounced features in both the longitudinal and transverse magnetores istivities rho(xx) and rho(xy) which cannot be understood within the simple framework of commensurability between cyclotron radius and superlattice pe riod. These resonances can be regarded as magnetotransport fingerprints of the complex unit cell. With the help of detailed numerical calculations usi ng classical linear response theory we can ascribe additional maxima in rho (xx) to closed orbits in the dotlike potential between four antidots. A pro nounced minimum in rho(xy) demonstrates the significance of open trajectori es. [S0163-1829(99)13835-9].