A Luminescence Study in the Pb1−xEuxSe System

Within the material class of lead chalcogenides a search for broader-gap materials for both confinement layers in heterostructures and barriers in MQW structures takes place. An optical study is presented for the most promising system Pb1−xEuxSe (0.02 ≦ x ≦ 0.36). Impurity-doped and defect-doped layers on BaF2 substrates grown by MBE are investigated by photoluminescence and photoconductive lifetime. The limits of weak and of strong excitation are realized by applying a N2 laser and a Q-switched Nd:YAG laser. From the luminescence gap versus composition an empirical Eg(x, T) relation is obtained. The observed dependence on composition of the stimulated and spontaneous emission are correlated with the lifetimes and with the composition-dependent laser thresholds.