Abstract
The incidence of thin-film-guided, in-plane unguided waves at oblique angles on straight discontinuities of dielectric slab waveguides, an early problem of integrated optics, is being re-considered. The 3-D frequency domain Maxwell equations reduce to a parametrized inhomogeneous vectorial problem on a 2-D computational domain, with transparent-influx boundary conditions. We propose a rigorous vectorial solver based on simultaneous expansions into polarized local slab eigenmodes along the two orthogonal cross section coordinates (quadridirectional eigenmode propagation QUEP). The quasi-analytical scheme is applicable to configurations with — in principle — arbitrary cross section geometries. Examples for a high-contrast facet of an asymmetric slab waveguide, for the lateral excitation of a channel waveguide, and for a step discontinuity between slab waveguides of different thicknesses are discussed.
Original language | Undefined |
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Pages (from-to) | 447-456 |
Number of pages | 10 |
Journal | Optics communications |
Volume | 338 |
DOIs | |
Publication status | Published - 1 Mar 2015 |
Keywords
- thin-film transitions
- vectorial eigenmode expansion
- slab waveguide discontinuities
- waveguide facets
- IR-92686
- Integrated Optics
- numerical / analyticalmodeling
- METIS-312452
- EWI-25287