Theoretical S-bend profile for optimization of optical waveguide radiation losses

High-density optical integrated circuits require curved waveguides with low radiation losses. The optimization of S-bend profiles that produce a minimum of pure bending losses is considered. The analytical profile that optimizes these losses in low-slope S-bends is presented, assuming an exponential representation for the bending losses per unit length. On the other hand, a numerical optimization procedure has been developed for curved waveguides with an arbitrary representation of the unitary bending losses. Some results are provided for LiNbO/sub 3/ waveguides, including a comparison between the optimal profile and other usual S-bend profiles.<
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