Can anybody suggest me how to model focusing Laguerre-Gauss beam (Vortex beam) in COMSOL waveoptics module?. I am looking for suggestion of equation in Cartesian coordinates?. Anybody has experience on this?
scattered field formulation is preferred in homogeneous medium. I need to model in substrate-air layer. All LG equations are in radial and azimuth coordinates which I can't use in Cartesian 3D model.