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Information × Registration Number 0214U002156, 0113U006046 , R & D reports Title Magneto-optical anisotropic suspensions of dye nanocrystallites. popup.stage_title Head Reznikov Yu.A., Registration Date 22-01-2014 Organization Institute of physics NASU popup.description2 Rapid development of the industry determines priority directions of research in various areas of physics. In particular, development and research of new materials and components, whose properties are at the junction of the different areas are of a great interest. One such promising area is the combination of soft matter physics and liquid crystals' physics, which gives rise to a whole new class of smart materials. These materials have increased sensitivity to electric, magnetic and optical fields, which opens up a wide range of new opportunities for their application. The main objective of this work is to develop and study novel materials (smart materials) by doping colloids of elongated dye nanoparticles with magnetic nanoparticles of various shapes and nature (ferromagnetic, paramagnetic, etc.). The main objects of study - colloids of dye crystallites in isotropic solvent (dodecane), and suspensions of nano-and microparticles of different nature on their basis. The project is based on the idea of controlling optical properties of dye colloidal solution doped by nano- and microparticles of various nature which will not significantly distort optical properties of the initial mixture, with electric, light and magnetic fields. This effect is caused by the spatial orientation of the magnetic particles' aggregates (formed due to dipole-dipole interaction between the nanoparticles) in an external magnetic field, and elastic interactions between particles and dye crystallites in the anisotropic areas of isotropic matrix, as well as in anisotropic matrix, which leads to reorientation of the liquid crystal director. The following main results have been obtained during the project: Basic properties of the behavior of the dye crystallites' suspension in the electric field have been studied. It has been shown that application of an external electric field causes redistribution of crystallites in the bulk of the suspension with their subsequent adsorption onto electrodes. Efficiency of the redistribution depends on the sign of the electrode potential, and is proportional to the electric field intensity and duration of its application. A model of redistribution of crystallites in a constant electric field has been proposed. The experimental setup for measuring ultra-small phase shifts using Senarmont method has been developed. This setup contains two main parts: electromagnet and optical recording unit. Major characteristics of the experimental setup: - electromagnet produces magnetic field in the range from 0 to 950 mT. - optical setup allows to measure very small values of phase retardation and birefringence ?n = 2 ? 10-7, with absolute and relative error of 0.01-0.05 deg and 1%, respectively. The technique for creating stable suspension of magnetic particles in suspension of dye crystallites' in a solvent has been proposed. All the results are obtained for the first time and can be used to develop a fundamentally new devices for information recording and display on the basis of lyotropic liquid crystal systems. Suspensions doped by magnetosensitive particles can be used for visualization of weak magnetic fields. Product Description popup.authors Булуй Олександр Григорович Креденцер Сергій Вікторович Резніков Юрій Олександрович Шеремет Ніна Василівна popup.nrat_date 2020-04-02 Close