Maxwell’s equations are reformulated to describe electromagnetic propagation along weakly guiding fibers of arbitrary refractive-index profile. The reformulation is particularly powerful for solving radiation from sources or scatterers within the fiber, leading to the most concise expressions possible. For example, radiation from sources in weakly guiding fibers is found by an elementary modification of the standard method for determining radiation from sources in free space. When the source has circular symmetry, the radiation field equals the free-space result multiplied by a factor that accounts for the presence of the fiber. Detailed examples are given for point and tubular sources.
© 1980 Optical Society of America
Allan W. Snyder, "Weakly guiding optical fibers," J. Opt. Soc. Am. 70, 405-411 (1980)