Zeeman studies of photoluminescence of excited terminal states of a bound-exciton-donor complex in GaAs

A bound-exciton-donor complex has been studied in GaAs by photoluminescence, using krypton-laser excitation (6471 Å). Observations of a large number of transitions between excited and terminal states in the field range from 12 to 40 kG are reported for the first time. Neither the perturbation nor adiabatic schemes appear to be applicable to present measurements. We present a phenomenological scheme which accounts well for our data. The donor ionization energy of 5.77 ± 0.08 meV has been determined experimentally from the $n=2\mathrm{}$ and $n=3\mathrm{}$ excited states. This value yields an electron effective mass of $m_e^{*}=0.66\mathrm{}$ in close agreement with values obtained theoretically.