Functional Laser Dyes

Polymers with specific functionalities can be realized by incorporating various dopants, such as laser dyes, rare earth ions, quantum dots, and functional chromophores into the host polymer. Chromophores are molecules or chemical groups as part of a larger molecule, and they have characteristic absorption bands in the... 

In xanthenes, even if all one-photon allowed transitions are also two-photon allowed, the shape of the bands and their relative intensities are very different in the IPA and 2PA spectra [76,78]. This is not the case for other laser dyes and chromophores, for which the two spectra are almost identical (if represented as a function of the total transition energy), showing peaks in the same position and with very similar band shapes. Some example of chromophores in this category are coumarin 307 [78], coumarin 102 [80], 7-hydroxycoumarin [81], lucifer yellow [78], and cascade blue [78]. 

Laser flash photolysis has been performed with the halogenated derivatives in ethanol [374], Measurements of the triplet lifetimes as a function of dye concentration, laser power, and in the presence of electron donors allowed us to determine the rate constants collected in Table 17. 

The observation of luminescence from laser dyes by ECL methods offers the possibility of using this approach to create dye lasers. A laser operating by ECL would not require an additional pump laser, and enhanced power, tunability, and wavelength selection are additional factors. While the pumping rate achieved by ECL previously has been two orders of magnitude lower than the optimal, Horiuchi et al. have reported a device structure designed to enhance the ECL efficiency and realize laser action driven by ECL [67], This experiment is illustrated in Fig. 14. A pair of sputter-deposited platinum film electrodes were positioned facing each other 2 to 7 microns apart. One electrode functioned... 

Figure 6, Spectra, as a function of dye laser excitation frequency, of supersonically expanded Na.

Heptakis 6-0-t-butyldimethylsilyl-P-cyclodextrin, on reaction with 4-chloro-methyl-A -methyl-2-nitroaniline, affords the mono-3-substituted benzyl ether. P-Cyclodextrin carrying a 2-(naphthylmethyl) group at 0-6 exists with the aromatic rings within the cavity to an extent which is very temperature dependent. Temperature can therefore be used to control the degree of complexing of the aromatic system with a fluorescent naphthalene compound. Heptakis-[2,3-di-0-acetyl-6-deoxy-6-iodo]-P-cyclodextrin treated with 6-methoxycarbonyl-2-naphthol allowed access to the compound having naphthoic acid substituents at all of the primary positions, and this forms a very stable 1 1 complex with a merocyanine laser dye which is a mimic of the antenna function in photosynthesis and shows promise as a photochemical microreactor. Mono-[6-0-(8-qui-nolyl)]-P-cyclodextrin has been reported, and the stabilities of inclusion complexes with amino acid guests have been described. ... 

So-called dual-marker particles are functionalized with dye and magnetite simultaneously. Magnetite label can be detected in vivo by altering the contrast in magnetic resonance tomography experiments, while the location of the fluorescent dye can be investigated by fluorescence or confocal laser scanning microscopy [47 9],... 

Lin K-C, Doane T, Wang L, Li P, Pejic S, Kenney ME, Burda C (2014) Laser spectroscopic assessment of a phthalocyanine-sensitized solar cell as a function of dye loading. Sol Energy Mater Sol Cells 126 155-162... 

Once formed phosphonium salts could have a significant effect on cellular processes, particularly on mitochondrial function. Ph3PMe has been used as a probe to measure membrane potentials, for instance in thyroid cells lymphocytes Escherichia and human granulocytes The lipid-soluble cation distributes itself across the membrane in accordance with the membrane potential Monovalent lipophilic cations which have significant membrane permeability are concentrated in mitochondria. For instance the laser dye Rhodamine 123 has been used as a specific probe for the localisation of mitochondria in living cells It has also been shown to have in vivo antitumour activity ... 

Composite glasses prepared via the sol-gel technique are of high optical quality and large monolithic bulk forms can be made for various photonic functions [22,23,79,88,101-103] such as lasing, optical power limitation, nonlinear optical response, and so on. Figure 10.9 presents an example of a solid dye laser based on multiphasic composite monolith doped with BASF LFO-240 laser dye placed in optical resonator. 

As already mentioned, the organic dye rhodamine 6G was one of the first luminescent species studied, encapsulated in silica obtained by the SGM [4], It was also mentioned that one important observation at that time was related to the enhanced stability the organic molecule experienced in the xerogel host. Indeed, that first paper opened the road for a multitude of new optical materials involving organic functionalities. Sensors, dye lasers (visible and NIR), photochromic, nonlinear optics, and photovoltaic devices are some of the possible applications for these dyes containing OIH [11,92,93]. 

Fig. 16. Maximum achievable signal-to-noise ratio (SNR) on read-out of different writable optical data storage systems as a function of the writing energy (laser power) (121). SQS = Organic dye system (WORM) PC = phase change system (TeSeSb) MO = magnetooptical system (GbTbFe). See text.

Selenium and selenium compounds are also used in electroless nickel-plating baths, delayed-action blasting caps, lithium batteries, xeroradiography, cyanine- and noncyanine-type dyes, thin-film field effect transistors (FET), thin-film lasers, and fire-resistant functional fluids in aeronautics (see... 

Further modification of the above nanostructures is useful for obtaining new functional materials. Thirdly, we apply the dopant-induced laser ablation technique to site-selectively doped thin diblock copolymer films with spheres (sea-island), cylinders (hole-network), and wormlike structures on the nanoscale [19, 20]. When the dye-doped component parts are ablated away by laser light, the films are modified selectively. Concerning the laser ablation of diblock copolymer films, Lengl et al. carried out the excimer laser ablation of diblock copolymer monolayer films, forming spherical micelles loaded with an Au salt to obtain metallic Au nanodots [21]. They used the laser ablation to remove the polymer matrix. In our experiment, however, the laser ablation is used to remove one component of block copolymers. Thereby, we can expect to obtain new functional materials with novel nanostmctures. 

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