MAGNETOPHONON RESONANCES IN QUANTUM WIRES

We have investigated the magnetotransport properties of quantum wires which were fabricated on high-mobility GaAs-GaAlAs modulation-doped heterostructures using laser holography and electron beam lithography. For low temperatures, regular Shubnikov-de Haas oscillations and an additional magnetoresistance peak are observed; the peak occurs each time the cyclotron diameter matches the wire width. For high temperatures (106 K < T < 175 K), however, all these peaks are washed out and new magnetoresistance structures are revealed; these are due to the occurrence of magnetophonon scattering in the wire, scattering which is used to determine the 1D quantization energies.