Determination of the topological charge of a bessel-gauss beam using the diffraction pattern through of an equilateral aperture

Abstract

The topological charge TC of an electromagnetic wave is relate with their wavefront spatial distribution. Electromagnetic waves with factor azimuthal exp(ilθ) in its phase, have TC integer (l=m) or non-integer (l=M). These electromagnetic waves with a well-defined of TC can be produced in the visible regime by computer generated holographic masks with fork shaped. In this paper, we study the formed triangle lattice distribution in the intensity Fraunhofer regime using numerical simulations of the Bessel-Gauss beams with integer and non-integer TC. The beam is diffracted by equilateral triangular aperture to measure both their sign and magnitude. In addition, we showed the experimental results of the intensity in far field regime product of diffraction of Bessel-Gauss beams with integer and noninteger TC by the equilateral triangular aperture. Partial and qualitative explanations have been proposed for the diffraction of electromagnetic beams with topological charge. This paper presents a complete analysis for qualitative and quantitative explanation of diffraction of a beam with topological charge by a triangular aperture. The results of such diffraction are obtained by numerical simulation or experimentally.