Wavelength flattened directional couplers: a geometrical approach
arXiv:0906.3975 · doi:10.1364/AO.42.007141
Abstract
A new approach to design wavelength insensitive optical power splitter is presented. First coupled-mode theory is cast in operatorial form. This allows to solve the equivalent of coupled differential equations as simple limits. The operators are then represented on a generalized Poincare sphere, and the resulting graphical tool is applied to different structures, giving a clear interpretation of previous results in literature as well as hints on how to find improved solutions.
30 pages, 13 figures