We have investigated the magnetotransport properties of quantum wires
which were fabricated on high-mobility GaAs-GaAlAs modulation-doped he
terostructures using laser holography and electron beam lithography. F
or low temperatures, regular Shubnikov-de Haas oscillations and an add
itional 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 m
agnetoresistance structures are revealed; these are due to the occurre
nce of magnetophonon scattering in the wire, scattering which is used
to determine the 1D quantization energies.