MAGNETOPHONON RESONANCE IN QUANTUM WIRES

Magnetophonon resonance effects in quantum wires are discussed. In a narrow quantum wire with a parabolic confinement potential, energy spacing HBAROMEGA, the magnetoconductivity exhibits extrema at resonance NHBARsquare-rootomega(c)2 + OMEGA2 = HBARomega0, where omega(c) = eB/m* and N = 1, 2, 3, ... The magnetoconductivity is found to consist of two dominant terms, the one sigma(e - ph), due to the scattering of electrons located near the center of the quantum wire by LO phonons resulting in maxima of the magnetoconductivity at resonance, and the other, sigma(po) due to the disturbance of the skipping motion of electrons near the edge of the quantum wire giving rise to minima in the magnetoconductivity. Experiments have been carried out in quantum wires with different structures, and revealed maxima in the magnetoresistance (rho(xx) = 1/sigma(xx)) in the temperature range 100-200 K, which indicates the term sigma(po) dominates. Determination of the energy spacing and the effective mass is discussed.