Scattering time in GaAs/AlGaAs narrow wires in the presence of magnetic field

Magnetoresistance measurements have been performed in narrow GaAs/AlGaAs wires in order to study the scattering process in mesoscopic wires. Amplitude analysis of the Shubnikov -de Haas oscillations shows that electrons have two scattering times, depending upon the magnetic field range. The critical field which separates these scattering times seems to be determined by the relation between the wire width and the electron cyclotron radius. This effect is discussed in terms of the electron trajectories in a wire under the magnetic field.