Infrared-absorption line shapes of shallow donors in cylindrical quantum-well-wire structures

A theoretical study of the intraimpurity infrared-absorption properties associated to donor-doped cylindrical GaAs–(Ga,Al)As quantum-well wires is presented. Donor binding energies and envelope wave functions are calculated within a variational scheme in the effective-mass approximation, and line strengths for intradonor transitions to excited states of 2s-, 2pz-, and 3pz-like symmetries are obtained for different photon polarizations and for donor positions varying along the radial direction of the wire. The donor-related absorption coefficients are evaluated in the case of 1s→2pz and 1s→3pz transitions for z-polarized radiation, and for different donor profiles in the quantum wire.