The electro-optical behavior of SrS : Ce electroluminescent devices under photonic excitation

The electro-optical behavior of the SrS:Ce electroluminescent devices under pulsed photonic excitation in the lower energy absorption band of Ce3+ was analyzed below the electroluminescence threshold voltage for a rectangular electric pulse. The photoluminescence quenching due to the ionization of t he Ce3+ ions under the electrical field increases with the applied voltage (40% at the threshold). Delocalization of involved electrons is responsible for emissions at the trailing edge of the electric pulse and for emissions during the following pulse. These emissions do not restore the level of th e photoluminescence without applied voltage. These different emissions allo w detailed study of energy trap levels for each insulator/SrS interface. An interpretation of the photoluminescence quenching is proposed (C) 2000 Ame rican Institute of Physics. [S0021-8979(00)08901-5].