Excitonic photoluminescence quenching by impact ionization of excitons and donors in GaAs/Al(0.35)Ga(0.65)As quantum wells with an in-plane electric field

We present a detailed experimental study on photoluminescence quenching due to exciton and donor impact ionization by accelerated electrons under an in-plane nanosecond duration electric field created in GaAs/Al(0.35)Ga(0.65)As quantum wells. From the photoluminescence transients measured by the time-correlated single-photon counting technique, we have determined the experimental conditions under which donor impact ionization can have an influence on quenching of the excitonic photoluminescence. The coefficient of twodimensional exciton impact ionization has been estimated; its dependences on the applied electric field, lattice temperature, and width of the quantum wells are given.