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The synthesis of new materials of hybrid character (organic-inorganic) doped with dyes results highly attractive like active medium in solid state laser in which the excellent thermal properties of the inorganic glasses with the excellent optic properties of the polymeric materials could be combined. Through a simultaneous synthesis process of sol-gel policondensation of the inorganic TEOS during the free radical polymerization of the organic part (vinylic or acrylic monomers with OH groups), since the presence of this -OH side groups in the organic monomer can participate in the policondensation process of silanols, hybrids monoliths were able to be obtained as solid-state dye laser matrices. The synthesis and characterization of new hybrid matrices were carried out incorporating pirromethene 567 (PM567) into polymers of 2-hydroxyethyl methacrylate (HEMA) and copolymers of HEMA and methyl methacrylate (MMA) with different weight proportions of the inorganic component, tetraethoxysilane (TEOS). The first results obtained with this new materials are indicave that the addition of low proportions of TEOS into the polymer P(HEMA/MMA 1/1) increases its thermal stability reducing the thermal degradation of the dye and, consequently, improving significantly its laser action. In fact, some of the results achieved with these new materials represent the best photostability reached to date for PM567 incorporated into inorganic and hybrid materials and, taking into account the experimental pumping conditions, improve or at least, compare well, with the lasing properties of the dye embedded in other host polymeric matrices.La síntesis de nuevos materiales de carácter híbrido (orgánico-inorgánico) dopados con colorantes resultan altamente atractivos como medio activo en láseres de estado sólido ya que permiten combinar las excelentes propiedades térmicas que presentan los vidrios inorgánicos con las excelentes propiedades ópticas que presentan los materiales polímeros. Mediante un proceso simultaneo de policondensación sol-gel y de polimerización de la parte orgánica (monómero vinílico ó acrílico con grupos OH), de forma que los grupos –OH del monómero orgánico participen también en el proceso de policondensación, hemos conseguido obtener monolitos válidos para su aplicación como láseres de colorante en estado sólido. Se ha llevado a cabo la síntesis y caracterización de nuevas matrices híbridas incorporando pirrometeno 567 como colorante láser (PM567); combinando polímeros de metacrilato de 2-hidroxietilo (HEMA) y copolímeros de HEMA y metacrilato de metilo (MMA) con diferentes proporciones en peso respecto al componente inorgánico (TEOS). Los primeros resultados obtenidos con estos nuevos materiales demuestran que la presencia de pequeñas proporciones de TEOS en copolímeros de p(HEMA/MMA 1/1) aumentan la estabilidad térmica del colorante mejorando significativamente su acción láser. De hecho, algunos de los resultados alcanzados con estos nuevos materiales mejoran, significativamente, las fotoestabilidades alcanzadas para el PM567 incorporado en otras matrices inorgánicas e híbridas, así como en muchas de las matrices orgánicas seleccionadas como hospedadores para este colorante.

A systematic study to relate the laser action from dyes doped into monolithic hybrid matrixes with the structural morphological, optical and a thermal property of the host materials was conducted. The thermal properties of these materials, together with the high homogeneity revealed by atomic force microscopy (AFM) images, even in compounds with high silica content indicate their microstructures to be a continuous phase, corresponding to the polymer matrix, which traps the silica component at molecular level.

Research on prryomethene 567 dye is examined in detail in terms of its laser performance, when it is used in methyl methacrylate copolymers.

The fluorescence and lasing properties of Coumarin 540A dye molecules in solutions with different viscosities were investigated. The effects of different polymerization techniques, dye concentration levels and the composition of the polymeric host media were also analyzed. Results showed that the lasing and fluorescence quantum yield efficiencies declined when the viscosity of the solution was increased, suggesting that the rigidity of the medium had a significant effect on the radiative processes.

The 157 nanometer laser ablation study of crosslinking monomers such as polyhydroxybutyrate (PHB) and polytetrafluoroethylene (PTFE) reveals the nature of dependence of the ablation process on the polymer structure. The application of Beer-Lambert's law and a kinetic model of moving interface to the ablation study reveals the process of ablation in these monomers. All the polymers exhibit an identical photoetching mechanism when subjected to ablation.

The lasing properties of a number of newly synthesized 2-(2 prime-hydroxyphenyl)benzimidazole derivatives copolymerized with methyl methacrylate or dissolved in poly(methyl methacrylate) and pumped with an N2 laser are reported. The radiation mechanism is based on the intramolecular proton-transfer in the electronic excited state. Both the lasting efficiency and the dye photostability increase significantly when the proton-transfer chromophore is covalently bound to the polymeric chain, and energy-conversion efficiencies comparable to those obtained in liquid solution are demonstrated.

Bichromatic laser emission from dipyrromethene-based solid-state dye lasers is reported. The dependence of this dual emission on different factors and its origin and causes are discussed in the light of different models proposed in the literature. Our experimental results indicate that the long-wavelength emission can be explained in terms of reabsorption/reemission effects and inhomogeneous broadening of the S0-S1 transition. The short-wavelength emission corresponds to the usual S0-S1 transition and dominates at low dye concentration. [ABSTRACT FROM AUTHOR]

We report on the synthesis, characterization, and physical properties of modified polymeric matrices incorporating silicon atoms in their structure and doped with laser dyes. When the silicon-modified organic matrices incorporated pyrromethene 567 (PM567) and pyrromethene 597 (PM597) dyes as actual solid solutions, highly photostable laser operation with reasonable, nonoptimized efficiencies was obtained under transversal pumping at 532 nm. At a pump repetition rate of 10 Hz, the intensity of the laser emission remained at the level or above the initial lasing intensity after 100 000 pump pulses in the same position of the sample, corresponding to an estimated accumulated pump energy absorbed by the system of 518 and 1295 GJ/mol for PM567 and PM597, respectively. When the pump repetition rate was increased to 30 Hz, the laser emission of dye PM567 decreased steadily and the output energy fell to one-half its initial value after an accumulated pump energy of 989 GJ/mol. Dye PM597 demonstrated a remarkable photostability, and under 30 Hz pumping the laser emission from some samples remained stable after 700 000 pump pulses in the same position of the sample, corresponding to an accumulated pump energy of 17 300 GJ/mol. Narrow linewidth operation with tuning ranges of up to 31 nm was obtained with both pyrromethene dyes when some of the samples were incorporated into a grazing-incidence grating oscillator. [ABSTRACT FROM AUTHOR]