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Polarization singularities in the self-focusing of an elliptically polarized laser beam in an isotropic phase of cholesteric liquid crystal close to the temperature of phase transition

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 نشر من قبل Georgy Shishkov
 تاريخ النشر 2020
  مجال البحث فيزياء
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The work is devoted to the self-action of laser beams propagating in the isotropic phase of a cholesteric liquid crystal near the transition temperature to the mesophase in a wide range of parameter values characterizing the nonlocality of the nonlinear optical response of the medium, defocusing in the medium, the power of incident laser radiation and diffraction in the liquid crystal. The origin of the primary singularities of both polarization components of radiation in a wide range of parameters of radiation and the medium is investigated for different values of the parameter characterizing the nonlocality of nonlinear optical response in chiral medium. For each of the values, the visibility diagrams of the primary singularities of both polarization components are plotted depending on the parameters of the medium and radiation, and their asymmetry is found.

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