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Information × Registration Number 0218U002357, 0117U003544 , R & D reports Title The limits of applicability of coupled waves model for the lasing in cholesteric liquid crystals activated by dyes. popup.stage_title Head Mykytiuk Taras Volodymyrovych, Registration Date 16-02-2018 Organization Institute of physics NASU popup.description2 Аn object of the researches are steroidal cholesteric liquid crystals (CLC), which are mixtures of cholesterol esters, and induced CLC, which are mixtures of nematic and twist admixture, activated by organic dyes, a aim of the research studying the mechanism of laser generation in steroid and induced CLC; study of threshold and spatial characteristics of laser generation in such CLCs; clarification of the bounds of the application of the theory of coupled waves and the theory of photonic crystals to explain the laser generation in CLC, methods of researches are optical spectroscopy, including polarization, laser spectroscopy. Theoretical and practical results are: Spectroscopic and laser properties of planar textures of steroidal CLC for different orientations of the surface layers of molecules on the substrates have been studied. A trough in the center of the SR band for perpendicular orientation of the surface layers on the substrates, which indicates the presence of a defect in the spiral of CLC, was observed. It is shown that the nature of the ring structure in the beam of the generation of a CLC laser is due to the generation of modes that are distributed at discrete angles to the resonator axis. Novelty - It was established that for steroid CLC with low birefringence the characteristics of the laser generation could be explained by the model of the coupled waves of Kogelnik and Shenk. For the induced CLC with the same birefringence the spectral characteristics of the generation can be explained by the model of photonic crystals, which envisage the laser generation at the edge of the SR band. Effectiveness of implementation - has not been implemented yet; sphere (industry) of application - Laser and Optoelectronics. Product Description popup.authors Микитюк Тарас Володимирович popup.nrat_date 2020-04-02 Close