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Information × Registration Number 0220U100847, 0117U000802 , R & D reports Title Generation and spatial control of optical vortices at acoustooptical diffraction taking into account the acoustooptical anisotropy of low-symmetry crystals popup.stage_title Head Vlokh Rostyslav O., Доктор фізико-математичних наук Registration Date 28-01-2020 Organization Vlokh Institute of Physical Optics popup.description2  The project is devoted to the optimization of geometry of acousto-optical (AO) interaction in low-symmetry crystals and to the development of principles of spatial control of optical vortices (OV) at AO diffraction. All piezooptic and photoelastic coefficients (PEC) of rhombic Tl3AsS4 and monoclinic triglycine sulfate crystals were determined. The PEC of KGd(WO4)2 and Sn2P2S6 monoclinic crystals were determined by Dickson – Cohen method. The anisotropy of elastic properties of rhombic (Tl3PSe4) and monoclinic (TlInS2) crystals was investigated. The method of anisotropy analysis of acousto-optical figure of merit (AOFM) of low-symmetry crystals is developed. Analytical ratios for strain tensor components for acoustic waves (AW) with arbitrary direction of wave vector in crystals were obtained. The influence of AW polarization deviation from pure modes on the anisotropy of AOFM is analyzed. Testing of the method on crystals of rhombic and monoclinic syngonics showed significant anisotropy of AOFM. The geometries of isotropic and anisotropic AO interactions with maximal AOFM values were determined, in particular in Tl3AsS4 crystals - 2181×10–15 s3/kg and 1990×10–15 s3/kg, in Tl3PSe4 - 280010-15 s3/kg and 1880010-15 s3/kg, respectively. It was firstly shown that phase structure and spatial profile of optical beam, which transfer the OV, remain at AO diffraction that allow to control the spatial position of the OV by AW frequency changes. The formation of OV with fractional charges at AO Bragg diffraction was experimentally revealed. The OV network arises in a wide diffracted optical beam as a result of reflection from a thick AO lattice containing split and forked bands. The changes in AW frequency result in the deviation of wide optical beam containing array of OV. It was shown that diffracted optical beam which propagates along one of the optical axes of biaxial crystals will transfer OV, the spatial position of which can be controlled by the change of AW frequency Product Description popup.authors Adamenko Dmytro I. Boyko Vitaliy T. Vlokh Rostyslav O. Dudok Taras G. Kostyrko Myroslav Ye. Kryvyy Taras T. Krupych Oleg M. Kushnir Oleh S. Martyniuk-Lototska Iryna Yu. Romanyuk Galyna M. Say Andriy S. Skab Ihor P. Smaha Ihor M. popup.nrat_date 2020-04-02 Close