Split Step Parabolic Equation Analysis of Coupled Dielectric Waveguides
The propagation phenomena in parallel coupled slab waveguides is investigated in terms of the Split Step Parabolic Equation Method (SSPEM) and the computed eigenvalues and the coupling coefficients are compared with the exact solution. Conventionally, couplers are excited from one port and the power as it propagates along the structure is transferred periodically back and forth between the waveguides and the period L is referred to as the beat length. In weakly coupled structures the eigenvalues of the propagating surface waves appear in rather closely spaced pairs thereby severly reducing the accuracy in determining the beat length. An alternative use of SSPEM may then be utilized for improved accuracy, wherein one determines the initial field in such a way as to excite only two modes of the coupler and determines L utilizing the perfect imaging properties of the waveguide.
Sevgi, Levent and Topuz, Ercan (1995) "Split Step Parabolic Equation Analysis of Coupled Dielectric Waveguides," Turkish Journal of Electrical Engineering and Computer Sciences: Vol. 3: No. 2, Article 4. Available at: https://journals.tubitak.gov.tr/elektrik/vol3/iss2/4