Double Raman resonances induced by a magnetic field in GaAs-AlAs multiple quantum wells

Abstract
A strong enhancement in the intensity of the Raman resonance profile has been observed in GaAs-AlAs multiple quantum wells, when the energies of different transitions are tuned by an external magnetic field. This finding is interpreted as double Raman resonances corresponding to some excited states and the ground state of the light-hole exciton as incoming and outgoing channels, respectively. Our results are best understood by assuming an exciton-phonon scattering mechanism instead of the usual free-electron–phonon interaction.