Bessel Beams in Crystals with Optical Activity

When considering optical beams propagating in media with optical activity, using the example of a structurally stable Bessel-Gauss launch, it is shown that in media without active birefringence, it is possible to create a single optical vortex in one of the polarization components of the beam. Mutual transformation between the components is due to the optical activity of the medium for both azimuthal and radial field components. The stable state of the isotropic point is due to the absence of external disturbances of the beam, and in the presence of external disturbances by the active medium, the isotropic point is destroyed. Linear activity and the presence of birefringence are related to each other and affect the isotropic point. The structure of fields in a medium with optical activity is very similar to the structure of Bessel-Gauss beams and can be controlled by them using external disturbances.