Magnetoconductivity in a mesoscopic antidot array

We describe studies of magnetotransport in antidot arrays formed by focused ion-beam implantation. This shows the dominant role played by interconnects between dotlike reservoirs. Two separate Shubnikov–de Haas periodicities are observed at high and low fields, which allow separate measurements of the depth of the reservoirs and the interconnects. A large negative magnetoresistance is observed at low fields, which is interpreted as being due to the formation of propagating edge states as the field increases.