Full vector analysis of two-dimensional angled and coated optical waveguide facets

Analysis of coupled rib and buried waveguides for efficient mode-spot converters

“…Therefore, the transform of the field in region II can be written as and that of the field in region IV as N Ep,,r (s, y) = g(s) + >JB1e (s) exp('(y +b')) (10) i=1 whereb' = (a'+d).…”

“…Although there are several versatile numerical methods, such as Finite Differences (FD) and Finite Elements (FE), which are slraightforward to apply and can provide high accuracy, their relatively long run-times make them quite inefficient, either within an iterative design process or when the structure to be analysed has large dimensions as in the present case. In these situations accurate semi-analytical approaches such as the Spectral Index (SI) [5,6,7] or Free Space Radiation Mode methods [8,9,10] are often more suitable for design, rapidly yielding excellent results. The novel spectral method developed here for the analysis of the mode spot tapers described above, successfully combines the Spectral Index (SI) method [5], previously restricted to the analysis of single and coupled rib waveguides, and the Free Space Radiation Mode method (FSRM) [8], previously used for the analysis of low contrast buried waveguides.…”

Excitation of an Open Cavity via HE11 Excited Single Mode Optical Fiber for a Fabry-Perot Interferometer

“…Diffraction from rectangular waveguide ends has been studied thoroughly in literature [4]- [6]. For circular geometry, the reflection of weakly guided modes from an uncoated fiber end was studied numerically in [7], while reflection from smoothed shaped cores of uncoated fibers was studied using semi-analytic methods [8].…”

Full vector analysis of optical fibre facet

“…With the view to simplify the analysis, 2D Fourier transform is applied to all field components in equations (5,6). In order to solve the system (4)-(5) for the modal reflectivities R,,, the radiation field can be expressed as …”

“…Very low facet reflectivities are most commonly achieved using layered antifreflection coatings (AR) or angling the facet [2], 133. The problem of design and optimisation of optical waveguide facets is now well elaborated for rectangular waveguides [4], [5], including scalar as well as vector analysis [6]. Optical fibre facets were modelled in scalar approximation considering only guided mode diffraction at the end or 'fibres [7], [8].…”