Electric Field-Induced Quenching of Photoluminescence from Ir(PPY)₃-Doped PVK

We study the photoluminescence (PL) and the PL dynamics of Ir(PPY)₃-doped poly(N-vinylcarbazol) (PVK) under the modulation of an electric field. The results show that the electric-field-induced quenching of PL from Ir(PPY)₃-doped PVK mainly comes from the dissociation of excitons in the chains of PVK. There is no significant difference in the excited state lifetime of Ir(PPY)₃ to be observed under the different applied negative biases. Our experiments demonstrate that the excitons attached to the molecules of Ir(PPY)₃ are very stable.