Lasing efficiency of dyes incorporated into a nanoporous glass-polymer composite

Abstract

We have used microsecond coherent pumping to study the lasing efficiency of active elements based on a nanoporous glass-polymer composite activated by organic dyes, as a function of the spectral composition of the pump within the main absorption band of the dye. We have shown that under the indicated excitation conditions, the lasing efficiency can exceed 40% and can be comparable with the lasing of liquid elements.Introduction. One disadvantage of lasers based on dye solutions is some inconvenience in operation associated with the fact that the active medium for this type of laser is a liquid. At the end of the 1960s, it was attempted to overcome this disadvantage using solid-state elements based on poly(methyl methacrylate) [1]. A disadvantage of these elements is their very low radiation resistance. Progress in this area began to be made in the 1980s after creation of solid-state matrices with high radiation resistance [2][3][4], and to date significant advances have been made in the field of solid-state dye lasers [5][6][7][8][9][10][11][12][13][14][15]. This is connected first of all with synthesis of new dyes and secondly with improvement of methods for introducing the dye into solid-state matrices [6]. Many authors use various approaches to composite solid-state systems. In [7], the lasing efficiency was determined as a function of the intensity of excitation and the laser photostability of gel systems with dyes. It was shown that the efficiency of conversion of the pump radiation and laser photostability of the dyes in composite gel systems is higher than in simple gel matrices. In [8], the lasing properties of rhodamine 6G (the chloride and the perchlorate) were studied in synthesized hybrid polymers based on an organic polymer (methyl methacrylate with hydroxyethyl methacrylate) and an inorganic precursor (tetraethoxysilane). It was shown that active media based on hybrid polymers have significantly higher operating life compared with active media based on organic polymers, which is associated with formation of an inorganic nanostructural network in them and consequently with an improvement in the thermooptical properties of the material and weakening of the thermally initiated process of decomposition of the active molecules. In [9], a technology was developed for obtaining active polymeric optical fibers doped with organic dyes. It was shown that the lasing efficiency of rhodamine 11B in a polymeric optical fiber with cw pumping may be as high as 36%. In [10][11][12], the spectral luminescence and lasing characteristics were studied for solid-state active media based on laser dyes of different classes (coumarins, rhodamines, paraterphenyl) emitting in the visible and UV regions and incorporated into silicate bulk matrices, gel matrices, and thin films. It was concluded that use of such elements was promising in fast conducting devices and in design of microlasers.In [13][14][15][16], new active elements are proposed that are based on a dye-activated nanoporous glass-polymer composite (NPG-P). In [13,1...

New laser dyes based on 3-imidazopyridylcoumarin derivatives

“…As a result, generation in the spectral range from the near UV to the near IR has been achieved [2][3][4][5][6][7][8]. Recently liquid solutions have been replaced by solid-state matrices [9][10][11][12]. However, such a broad spectral range does not mean that dyes that generate with high efficiency, are photochemically stable to UV pumping, and have increased operational lifetimes are available over all ranges.…”

“…Spectral luminescent characteristics of dye solutions were studied on the nanosecond pulsed spectrofluorimeter that was described before [8]. Fluorescence decay times were measured using the laboratory setup operating in time-correlated single-photon counting mode that was described before [11].Generation parameters of EtOH solutions of coumarin dyes with microsecond pumping were studied in a dye laser converter (Fig. 1).…”