Grating-Assisted Fibre-Slab Couplers
نویسندگان
چکیده
Coupled-mode equations for an asymmetric fibre-to-planar optical coupling system, incorporated a grating structure are presented. A grating-assisted coupling coefficient is described. When the parameters of the coupler are such that there is no phase synchronism between the fibre and the slab modes, the grating enhances the coupling in both the resultant amplitude and phase modulation. However, when there is a phase synchronism between the two sets of guided modes of the circular fibre and planar slab structures, the effects of the grating structure are greatly reduced. The coupling features give the fibre-slab coupler another unique dimension of amplitude and phase modulation and thus increase the coupler design flexibility to achieve certain desired level of power transfer from one waveguide structure to the other and vice versa.
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