General approach for the sensitivity analysis and optimization of integrated optical evanescent-wave sensors

The optimization of integrated optical evanescent-wave sensors includes two parts. For optimal performance, we require waveguides with both maximal sensitivity to the measurand—the quantity intended to be measured—and minimal sensitivity to perturbations. In this context, fully numerical approaches are extremely powerful but demand huge computer resources. We address this issue by introducing a general and efficient approach, based on the formal derivation of analytical dispersion equations, to express and evaluate all waveguide sensitivities. In particular, we apply this approach to rectangular waveguides and discuss its accuracy and its use within sensitivity optimization procedures.