A detailed study of internal conical refraction phenomenon of Flattened Gaussian beams propagating in a biaxial crystal

By means of the internal conical refraction phenomenon, the transformation of input Flattened Gaussian beams (FGBs) through a biaxial crystal has been investigated in this paper. The effect of this phenomenon on these input beams leads to the formation of two bright rings separated by a dark ring in the focal plane. Analytical expressions of electric fields and intensity profiles of the considered light beams propagating in a biaxial crystal have been derived. Some numerical simulations are performed and discussed by studying the influences of some parameters as the input beam order, the ratio between the ring radius and the waist radius of the incident beam, and the propagation distance. The propagation of circularly polarized Gaussian beams in the considered optical system is also deduced as particular case in this work.