Analysis of multi-layer arrow planar waveguide for evanescent field enhancement in low-index media

The ARROW (Antiresonant Reflecting Optical Waveguide) waveguide is a basic component of integrated optical circuits. In this thesis, multi-layer ARROW planar waveguide is studied for the purpose of enhancing the evanescent field in low-index media. This leads to enhancing the sensitivity of optical detection in the low-index media. We have analyzed this structure using water as the low-index superstrate and investigated different aspects which include a study of the polarization properties, sensitivity and coupling loss using endfire excitation. The sensitivity of optical detection and power enhancement of the evanescent field in the low-index superstrate of the multi-layer ARROW waveguide is sufficiently increased as the core thickness of the multi-layer ARROW waveguide is decreased. Gaussian beam coupling problem which involves a single discontinuity is successfully analyzed using the Method of Lines (MOL). The Perfectly Matched Layer (PML) absorber is used to absorb the radiated fields from this discontinuities. The MOL with Higher-order approximations of the second derivative (∂2/∂x2) operator with appropriate interface conditions are used in the analysis.