| Two dimensional photonic crystal slabs are studied theoretically and experimentally for the application of refractive index sensing with a focus on increasing both quality factor and sensitivity simultaneously. An overview of simulation and experimental techniques, along with fabrication protocols used is given. Through the use of new wafer architectures which allow for an air substrate, sensitivity is enhanced in some cases by more than a factor of 2 from our previous studies. Combining this with a novel lattice proposed which greatly reduces fabrication tolerances, experimental quality factors above 10,500 are achieved while maintaining an experimental sensitivity of above 800 nm/RIU. The effects of a finite photonic crystal slab are studied through the group velocity of guided mode resonances, with an emphasis on zero-group velocity. Future applications of the designs proposed are discussed. |
