Numerical Analysis of a Long Period Waveguide Grating Sensor

In this work the authors treat from the theoretical point of view a refractive index sensors configuration based on the long period waveguide grating. This sensor works by coupling the radiation carried by the fundamental mode into the "leaky" modes of the silicon dioxide waveguide substrate. The change of the output intensity with the surrounding medium refractive index is analyzed for various parameters. The authors have investigated the methods for increasing the sensor performances and also the fabrication tolerance