Photoluminescence of Modulation Doping GaAs/Al_(0.27)Ga_(0.73)AsMultiquantum Well Structure

The photolumenescence spectra of modulation doing GaAs/Al0.27Ga0.73As multiquantum wellstructure were measured. There are a strong luminescence peak and several low energy weak peaksin the luminescence spectra. The strong one arises from transition of electron at ground state inwell to heavy hole and these low energy weak peaks may be attributed to transition of electron atDX centers in Al0.27Gh0.73As to SiAs atoms. On this view, we can come to the conclusion thatthe DX centers in St-doped AlGaAs appear as four levels and their activation energies are about0.35eV, 0.37eV, 0.39eV and 0.41eV, respectively.