Camposeo Andrea, Persano Luana, Del Carro Pompilio, Papazoglou Dimitris G, Stassinopoulos Andreas, Anglos Demetrios, Cingolani Roberto, Pisignano Dario
National Nanotechnology Laboratory of INFM-CNR,c/o Distretto Tecnologico, Università del Salento, via Arnesano, I-73100 Lecce, Italy.
Opt Express. 2008 Jul 7;16(14):10384-9. doi: 10.1364/oe.16.010384.
We report on the measurement of the longitudinal coherence of organic microcavity lasers based on a conjugated polymer. By using a modified Michelson interferometer configuration enabling single-shot measurements of the coherence length, the transition from spontaneous emission to lasing is investigated. The measured coherence length grows upon increasing the pumping fluence, saturating around 45 microm above threshold. At large fluences, possible thermal and photo-oxidation processes occurring in the gain medium limit the further increase of the coherence length. Our results are important for understanding lasing emission in organic microcavities and optimizing the device design and performances.
