| Abstract
| - The sol−gel technique was used to incorporate rhodamine 6GDN (Rh 6GDN) into thin layers of SiO2 andinto an organic−inorganic hybrid matrix (OIHM). The OIHM is composed of a mixture of SiO2 and anacrylic copolymer. The Rh 6GDN was also incorporated into poly(methyl methacrylate) (PMMA) matrices.To investigate the influence of the different matrices on the optical behavior of the Rh 6GDN-colored layerson glass substrates, the optical absorption and photoluminescence were measured and analyzed. The absorptionspectra show the presence of two main bands related to the monomer and dimer absorption, the relativeintensity of these band depends on the type of matrix and on the hydrolyzation/condensation time. The strongestluminescence intensity was observed when the dye was embedded in the PMMA matrix; it was 20% largerthan that observed in the OIHM layers. The weakest luminescence corresponds to the dye in the SiO2 matrix,which was up to 90% below the values observed when PMMA matrices were used. The absorption spectraof the dye show an unusual intense band at a wavelength of 310 nm when it is embedded in the PMMAmatrix. A band in this position, which emits at 308 nm, is desirable for excimer laser applications. A simplequantum mechanical model is used, which treats the dye molecules as two-dimensional potential wells fordelocalized electrons. The model fits reasonably well the experimental optical transitions determined fromabsorption and fluorescence spectra.
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