Baumann, S. M. Kalb, D. M. MacMillan, L. H. Galvez, E. J. Media 2: Propagation dynamics of optical vortices due to Gouy phase Originally published in Optics Express on 08 June 2009 (oe-17-12-9818) 08 June 2009;Optics Express;media;dynamic;Propagation;vortice;oe;Gouy phase 2009-06-08
    https://opticapublishing.figshare.com/articles/media/Media_2_Propagation_dynamics_of_optical_vortices_due_to_Gouy_phase/4939238
10.1364/OE.17.009818.m002