Topological Charge of a Coaxial Superposition of the Bessel-Gaussian Laser Beams

Here, we study a superposition of Bessel-Gaussian beams with topological charges (TC) m and n. We prove theoretically that continuous varying the amplitudes of the constituent beams allows controlling the TC of the entire superposition. We obtain the conditions, when the TC is equal to n or m. In the cross-section of such a superposition, there is an m-order optical vortex (if m