Optimization of buried type waveguide for single-mode operation

The optimization of buried type waveguide for single-mode operation has been done using effective index method (EIM) and finite difference utilizes alternating direction implicit (ADI) method. The waveguide dimension is 7x7 μm2. The waveguide structure with 0.35% of core-cladding relative refractive index difference operate as a single-mode waveguide in optical communication transmission window from λ = 1.3 μm to 1.55 μm. The cosine S-bend developed from the waveguide provides very low attenuation. Optimum longitudinal lengths are 1600 to 2000 μm for offset 15 μm with attenuation below 0.05 dB. Hence, the S-bend can be considered as a straight waveguide.