DYNAMICS OF PHOTOEXCITED STATES AND CHARGE-CARRIERS IN ORGANIC THIN-FILMS - ALQ(3)

We demonstrate a method for observing and analyzing the dynamics of ph otoexcited molecular states and charge carriers in organic thin films, by measuring simultaneously the transient photoluminescence and photo conductivity. We show experimentally in tris-(8-hydroxyquinoline) alum inum (Alq(3)) that exciton-exciton annihilation dictates the behavior of the photoluminescence and photoconductivity at high excitation inte nsities. The experimental results are corroborated by calculations bas ed on an exciton-exciton annihilation model. (C) 1996 American Institu te of Physics.