DC and far infrared experiments on deep mesa etched single and multi-layered quantum wires

Abstract

We discuss one-dimensional electronic systems (1DES) which have been realized by ultrafine mesa etching of modulation doped GaAs/AlGaAs heterostructures and multi quantum well systems. The electronic properties of these single and multilayered quantum wires can be characterized bh dc magnetotransport measurements. Quantum wires with 400 to 150nm wide electron channels exhibit typical energy separations of 1 to 3mev for the 1D subbands. The 1D subband separation is not directly observed in the far infrared (FIR) response, rather, resonances at significantly higher frequencies are observed, indicating a dominant influence of collective effects. This microstructure. The plasmon character is in particular manifested by the observation of layer-coupled plasmon modes with n resonances in n-layered quantum wires.