Optical vortices and the flow of their angular momentum in a multimode fiber
A. N. Alexeyev, T. A. Fadeyeva, A. V. Volyar Physical Department, Simferopol State University, Yaltinskaya 4, 333036 Simferopol, Ukraine
M. S. Soskin Institute of Physics, NAS Ukraine, 46 prospekt Nauki, Kyiv, 252028, Ukraine
Abstract. The problem of propagation of optical vortices in multimode fibers is considered. The structural changes experienced by the wave and ray surfaces in their transformation from the free space to a fiber medium are determined. The continuity equation is obtained for the flow of the vortex angular momentum in an unhomogeneous medium.