Photoluminescence in semimagneticZn1−xMnxTe

Abstract

Luminescence in photoexcited ${\mathrm{Zn}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ has been studied for three dilute alloy compositions ($x=0.001, 0.011, \mathrm{and} 0.016$) under a wide range of excitation and in zero external magnetic field. We find that the bound-exciton localization energy is composition dependent, evidently due to an exchange-induced contribution by the paramagnetic Mn ions. Under high-intensity excitation we have observed electron-hole plasma (EHP) emission from all the samples studied. For the line-shape analysis of the EHP emission, a simple model is introduced that takes alloy-compositional fluctuations into account. The EHP emission for the $x=0.001\mathrm{}$ material yields plasma parameters which are consistent with the formation of an electron-hole liquid, while in samples with higher Mn concentration there is no evidence for such formation.