Raman probe of classical magnetoresistance in doped GaAs/AlAs superlattices

The characteristical asymmetric shapes of the Raman lines caused by the collective plasmon–LO phonon excitations in heavily doped GaAs/AlAs superlattices were analyzed in order to separate the influence of the magnetic field on the spatial extent of the collective excitations and on their damping constant, which is attributed to the AC conductivity. It was shown that the magnetic field influences the damping of the plasmon-like excitations stronger than their spatial extent.