Impurity-related optical absorption spectra of GaAs-Ga1−xAlxAs cylindrical quantum-well wires

The optical-absorption spectra associated with transitions between the n=1 valence subband and the donor-impurity band and between the acceptor-impurity band and the n=1 conduction subband were calculated for GaAs-Ga1−xAlxAs cylindrical quantum-well wires of different radii. The distribution of impurities in the wire was assumed to be homogeneous and interaction between the impurities was neglected. The main features in the theoretical spectra were an absorption edge associated with transitions involving impurities at the center of the wire and a peak related to impurities at the edge of the wire. Calculations were performed for both infinite and finite potential barriers, and were compared with previous results in quantum wells of comparable dimensions.