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Information × Registration Number 0220U100166, 0119U101508 , R & D reports Title Development of highly efficient polymethine dies for passive Q-switch and passive mode locking of the neodymium-laser with generation wavelength 1060 nm popup.stage_title Head Ishchenko Oleksandr O., Registration Date 11-01-2019 Organization Institute of Organic Chemistry NAS of Ukraine popup.description2  Methods for synthesis of indolinines anelinated in different positions have been developed. New polymethine dyes (PD) based on benz[c,d]indole have been synthesized. Their optical spectra in ethanol and multicomponent polymer urethane composition were investigated. It is shown that the composition used differs favorably from polymethyl methacrylate and polyurethane acrylate, in which, as a result of solidification by the method of radical polymerization, there is a significant destruction of dyes. It is established that the relaxation times τ of the excited (enlightened) state of new PCs in ethanol are approximately the same as those of the dye 3274u, which is widely used for passive modulation of the Q-factor and synchronization of neodymium laser modes. The small sensitivity of the values of τ to the change in the chemical structure of the PC indicates that the major contribution to the deactivation of the excited state is made by benz[c,d]indole heterocycle. High values of  in the region of 1.05-1.08 microns at low relaxation times of the studied PCs allow them to be easily illuminated in lasers at low intensities (about 10 MW / cm2). It is found that as we move from ethanol solutions to the polymer matrix, the values of τ of the PC increase. This is explained by the decrease in the role of photoisomerization processes in the degradation of excitation energy, due to the increase in the structural rigidity of PC molecules in the polymer. It has been found that, despite the increase in the relaxation time of the synthesized PCs in the polymer matrix, their magnitudes are quite sufficient for the generation of short pulses in passive mode synchronization lasers. It has been found that the photoconductivity of new PCs in ethanol far exceeds that for the 3274y dye. This is due to the fact that they contain in the polymethine chain a saturated six-membered cycle that is much less reactive than the corresponding five-membered dye cycle of 3274u with respect to the ph Product Description popup.authors Ishchenko Aleksander A. Kulinich Andrii V. Kurdyukov Volodymyr V. Kurdiukova Iryna V. Slominskii Yurii L. Shandura Mykola P. popup.nrat_date 2020-04-02 Close