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Information × Registration Number 0219U001216, 0118U006339 , R & D reports Title Influence of defects of planar texture of cholesteric liquid crystals on characteristics of their lasing. popup.stage_title Head Mykytiuk Taras Volodymyrovych, Registration Date 18-01-2019 Organization Institute of physics NASU popup.description2 Аn object of the researches are steroidal cholesteric liquid crystals (CLC), which are mixtures of cholesterol esters, a aim of the research studying the characteristics of laser generation in cholesteric liquid crystals in the presence of defects of various types in its spiral structure.; investigation of the influence of boundary conditions on a defective layer on spectral and threshold characteristics of laser generation in CLC; comparison of experimental data with existing theoretical models of laser generation, 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; first obtained lasing in steroid CLC on bilayer specimens with small planar texture thicknesses; it is shown that the introduction of an isotropic layer into the spiral structure of a CLC leads to the disappearance of higher-order laser modes in the spectrum except for the main Bregg. Novelty - It was established that a defect can arise in the helix of CLCs made by viscous mixture of cholesterol esters at the mutually orthogonal director orientations at the orienting substrates. The defect manifests itself as a characteristic dip in the selective reflection (SR) band. It was established that single-mode generation can occur and be maintained when an isotropic defective layer is introduced into the CLC spiral. This method considerably improves the spectral purity of radiation emitted by a CLC laser. Product Description popup.authors Микитюк Тарас Володимирович popup.nrat_date 2020-04-02 Close