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Luminescence of Ga02A103As, highly doped with Si as an amphoteric impurity, was excited by an electron beam at liquid
nitrogen temperature. Two luminescence bands with photon energies of about 1 .8 eV and 2. 1 eV are observed, showing
peculiar intensity behavior when the external excitation current is switched between a high and a low value. While the highenergy
luminescence band shows a common intensity dependence proportional to the exciting current, the low-energy
luminescence band intensity diminishes when the beam current is increased. Such an opposite run of the cathodolurninescence
intensity at preselected spectral lines just by incrementing or decrementmg the electron beam current implies optoelectronic
switching properties. A study is carried out in order to determine the physical nature of the recombination transitions, and the
process, which leads to the surprising intensity vs. excitation behavior. Experimental results are analyzed by using a set of rate
equations for a free-to-bound and a donor-acceptor pair transition, whereby an AUGER impact ionization process between two
occupied neighboring acceptors and a pair-forming donor is incorporated. Under the particular situation of highly doped and
almost compensated semiconductors, a bound state may happen at high excitation levels, which involves a close donoracceptor
pair and a neighboring second donor or acceptor. The de-excitation behavior of such a bound state resembles
characteristics know from AUGER transitions, where an electron and a hole recombine and donate the annihilation energy to a
third particle, either a hole or an electron. The consequence is quenching of the radiative recombmation efficiency of the first
transition, and under certain circumstances an increase of the recombination intensity of a second channel, which incorporates
the thus liberated third particle. Theoretical and experimental results are in good agreement.
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