Gaussian beams with optical vortex of charge 2-and 3-diffraction by a half-plane and slit

In the paper, the half-plane diffraction of the Gaussian light beam containing double and triple optical vortex is examined. The analysis is based on scalar theory of diffraction in Fresnel-Kirchhoff approximation. Special attention is paid to the dynamics of the optical vortex within the diffracted beam. Some results for the case of diffraction by single slit are also presented.