Microwave-induced giant oscillations of the magnetoconductivity and zero-conductance state in 2D electronic Corbino disks with capacitance contacts

Using Corbino disks with capacitance contacts, the microwave photoconductivity of the 2D electron gas in selectively doped GaAs/AlAs heterostructures has been studied at 1.6 K in magnetic fields up to 0.5 T. The giant oscillations of the magnetoconductivity and zero - conductance state have been revealed in the samples exposed to microwave radiation at high filling factors similar to those earlier discovered in the 2D Corbino disks with ohmic contacts. The results demonstrate that the presence of ohmic contacts is of no importance for observation of the microwave - induced giant oscillations of the magnetoconductivity and zero - conductance state in the 2D electron system.