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Information × Registration Number 0212U000332, 0111U007202 , R & D reports Title Studies of optical edge and defect modes and low threshold lasing in chiral liquid crystals. popup.stage_title Head Tichonov E.A., Registration Date 01-02-2012 Organization Institute of physics NASU popup.description2 Аn object of researches is - cholesteric liquid crystals, activated by organic dyes, a research purpose is - a study of CLC quality planar texture on spectral and spatial characteristics of lasing in dependance of the substrate materials and the excitation intensity, methods of researches and apparatus are - optical spectroscopy, including polarization, laser spectroscopy, theoretical and practical results - the dependence of the spectral and spatial lasing characteristics of steroidal and induced dye doped CLC matrices from the director orientation on both substrates and the substrate materials. Difference of their spectral and spatial lasing characteristics it was shown. The appearance of rings in the spatial distribution of the lasing beam of the DFB- laser based on cholesteric liquid crystals with parallel director orientations on substrates associated with the high devergence of the longitudinal mode beam and multipath interference in Bragg structures, as the interferometer. For the case of the steroidal CLC under perpendicular orientation of the directors of on the substrates the ring structure in the beam does not appeared and all energy emission in the main central mode is concentrated even in a wide range of pumping. These features of the lasing point to lasing on the defect mode in photonic crystal, but so far failed to register a corresponding dip in the selective reflection spectrum as main characteristic for the defect spiral structure according to theoretical calculations. The relationship of the spectral and spatial characteristics of the lasing in steroidal CLC can be formulated as follows: as soon as in the lasing spectrum longitudinal modes of higher orders appear in the spatial pattern lasing a ring structure arises. The difference between the spectral characteristics of the lasing of induced cholesteric liquid crystals is that the quality of the planar texture and thickness of the layer is practically not affect the position of the spectrum relative to CR bands and their lasing spatial characteristics. Novelty - a practical novelty is the establishment of the relationship between the number of modes in the spectrum of lasing and the nature of the spatial pattern of its distribution for steroid CLC. efficiency of application - not prove up to now, a sphere of future application finds in laser and optronic technique. Product Description popup.authors Ільчишин Ігор Павлович Микитюк Тарас Володимирович Тихонов Евген Олександрович popup.nrat_date 2020-04-02 Close