Thickness dependence on sensitivity of guided-mode-resonance biosensors

In this letter, the waveguide thickness dependence on the sensitivity of the guided-mode resonance (GMR) biosensor has been explored by simulation. It is clarified the relationship between the resonant mode number and the the waveguide thickness of GMR biosensors. By increasing the waveguide thickness can not only introduce more higher-order guided modes but also reduce both the corresponding resonant bandwidth and the resonant peak wavelength shift. Its sensitivity can improved by carefully design the GMR structure and selected the resonant mode characteristics. Carefully design the GMR structure and selected the resonant mode, the sensitive of the two-layer GMR bio-sensor will be well improved.