THE DYE ACTIVATED POLYMERS WITH ADDED FINE SCATTERED PARTICLES AS NEW LASING MEDIA, V.Bezrodny, E.Tikhonov, Physics Institute of The Ukrainian Academy of Science; O.Prygodjuk, Vasil P.Yashchuk, Kyiv T.Shevchenko University, Glushkov av., 6, 03127 Kyiv, Ukraine. Strong scattering active media are the new group of lasing media. Lasing of such materials has some specific features: possibility of small volume generation, low threshold, action without cavity and, consequently, undirected radiation. The investigation of these media is of great interest. We have investigated the superluminescence and lasing spectra of dye activated (rhodamin 6G) polyvinylacetate samples with added fine particles under the different scatterer materials (SiO[2], Al[2]O[3], CeO[2] and synthetic diamond), various scatterers concentration and different pump intensity. The dependence of lasing bandwidth and maximum of lasing spectrum on the scatterer materials as well as scatterers concentration was observed. The lowest observed lasing bandwidth was about 5-8nm for highest diamond concentration (c=30%). Besides this we have noted the considerable dependence of lasing threshold on scatterers materials and on scatterers concentration. This property can be useful for the tuneable emitter development. The obtained threshold pump intensity of investigated sample was rather high (~10MWt/sm2) that was probably conditioned by inhomogeneity of scatterers concentration. Obtained results verified the possibility of lasing in these systems. The obtained spectral parameters are typical for multimode dye laser. To decrease lasing threshold and improve spectral parameters it is necessary to advance the sample creation technology.
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