Sensitivity optimization for the index sensors based on waveguide metallic photonic crystals through angle-resolved tuning

Abstract

An optical sensor device based on waveguide metallic photonic crystals for the detection of the environmental refractive-index change is investigated. The sensitivity of the device is found to be improved through optimizing the angle of incidence of the light. This is based on the overlap of the waveguide resonance mode with the most sensitive spectral position of the spectroscopic response of the localized surface plasmon. Experimental investigations were performed on the glucose/water solution with different concentrations. The measurement data verified the mechanisms for the optimization of the sensor sensitivity by adjusting the incident angle of the light, which show excellent linearity and high reproducibility.

Keywords:

• waveguide metallic photonic crystals
• localized surface plasmon
• waveguide resonance mode
• angle-resolved tuning
• refractive-index sensor

Acknowledgements

The authors acknowledge the National Key Basic Research Program of China (2013CB922404) and the National Natural Science Foundation of China (11074018, 11274031) for the support.