First observation of 2P-magnetoexcitons in GaAs/AlGaAs multiple quantum wells via two-photon absorption processes

Photoconductivity measurements of two-photon magnetoabsorption in GaAs/AlGaAs multiple quantum wells have been performed using a one-beam pumping technique. The splitting of 2P-exciton states in magnetic fields up to 6 T have been studied in Faraday configuration with the linear polarization parallel to the layers of the quantum wells. By applying a theory of linear-Zeeman effect in the hydrogen atom, effective masses for motion parallel to the quantum-well layers can be extracted from the data to be O.1Om for heavy holes and O.18m for light holes.