We introduce a method to estimate the coupling coefficients of the guided field amplitude and the corresponding angular bandwidth in a multimode slab waveguide. This scalar diffraction theory approach is simpler than the more rigorous electromagnetic treatment and is directly applicable to communications systems that use large (dimensions or numerical aperture) waveguides, as in substrate-mode interconnects. Moreover, this method provides conceptual insight as to a parameter’s effect on the field-amplitude mode distribution and angular bandwidth.
© 1998 Optical Society of America
(050.1940) Diffraction and gratings : Diffraction
(060.1810) Fiber optics and optical communications : Buffers, couplers, routers, switches, and multiplexers
(230.7400) Optical devices : Waveguides, slab
Shanalyn A. Kemme and Raymond K. Kostuk, "Scalar Diffraction Theory Approach to Estimating Multimode-Waveguide Field-Amplitude Mode Distributions," Appl. Opt. 37, 4399-4404 (1998)