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Information × Registration Number 0223U003084, 0121U109804 , R & D reports Title Generation of singular vector-vortex beams by parametric optics methods popup.stage_title Head Skab Ihor P., Доктор фізико-математичних наук Registration Date 29-03-2023 Organization OG Vlokh Institute of Physical Optics of the Ministry of Education and Science of Ukraine popup.description2  The occurrence of vector singularities of the acoustic field induced by inhomogeneous stresses is analyzed. It is shown that the mechanical bending stress can cause the appearance of a topological defect in the orientation of the eigenvectors of the Christoffel tensor with a force of ½ and the generation of a single-charged acoustic vortex for transverse acoustic waves. On the example of 3m symmetry group crystals the process of inverse collinear acousto-optical diffraction is considered for the case of the interaction of optical and acoustic waves, which transfer topological defects of their phase fronts generated by bending. The built-in topological defect of the phase front associated with the vortex has a strength determined by the sum of the topological defect strengths of the incident optical wave and the acoustic wave. The elastoacoustic effect caused by torsional stresses in LiNbO3 crystals is considered. It is shown that mechanical torsion can cause the acoustic singularity of the eigenvectors of the Christoffel tensor, and the torsion-induced "acoustic birefringence" is conically distributed in space, with an elliptical cross-section. This leads to the appearance of a single-charged acoustic vortex beam inside the crystal. A method of modulating the intensity of optical beams carrying the orbital moment with a modulation factor equal to 100% is proposed, which is based on the use of an incident Bessel beam of a higher order and a torsion-induced Bessel beam. It allows you to additionally change the charge of the vortex of the incident beam and creates new opportunities for quantum coding of information for information transmission with an increase in the volumes of encoded and transmitted information. The optical singularities of the vector field in liquid crystal nematic cells with circular planar and circular hybrid arrangements were experimentally investigated. Product Description popup.authors Vasylkiv Yuriy V Vlokh Rostyslav Orestovych Kostyrko Myroslav Yevgeniyovych Krupych Oleh M Skab Ihor P. popup.nrat_date 2023-03-29 Close