Photo-physical and lasing characterization of an aromatic diamine-xylylenecopolymer

A solution processable poly-condensation product of high glass transition t emperature containing 50 mol% electrically active triphenylamine dimer (TPD ) chromophores and 50 mol% non-conjugated alpha,alpha -diphenylxylylene (DP X) units in the main chain is studied for its photo-physical and lasing pro perties. This copolymer abbreviated as poly-TPD-DPX shows travelling-wave l aser action (amplification of spontaneous emission) as neat film on a fused silica substrate and in liquid solution when transversally pumped with pic osecond excitation pulses (wavelength 347.15 nm, duration 35 ps). Lasing oc curs at 419 nm for the neat film and at 405 nm for the polymer in 1,4-dioxa ne solution. The optical constants (absorption spectrum and refractive inde x spectrum) of the neat film are determined by reflection and transmission measurement. The absorption cross-section spectra and fluorescence quantum distribution spectra of neat films and 1,4-dioxane solutions are compared. The fluorescence quantum yields of poly-TPD-DPX neat films and 1,4-dioxane solutions are 0.16 and 0.66, respectively. (C) 2000 Elsevier Science B.V. A ll rights reserved.