STIMULATED-EMISSION FROM VACUUM-DEPOSITED THIN-FILMS OF A SUBSTITUTEDOLIGO(P-PHENYLENE VINYLENE)

The influence of the morphology on the light emission properties of va cuum-deposited polycrystalline oligo(p-phenylene vinylene) thin films under intense laser excitation was studied. The morphology of the thin films was varied by annealing just below the first melting point (cry stal-mesophase transition) and by crystallization from the isotropic m elt. Amplified spontaneous emission occurred within the individual dom ains and was only observed when the domain size was increased by therm al treatment. The amplified spontaneous emission threshold for the mel t-crystallized thin films was found to be comparable to that for conju gated polymer thin films. (C) 1998 American Institute of Physics.