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Updated: Feb 12, 2026
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
Evanescent Properties of Optical Diffraction from 2-Dimensional Hexagonal Photonic Crystals and Their Sensor
Yu-Yang Liao1, Yung-Tsan Chen2, Chien-Chun Chen3
1Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 1kin6, Taiwan. yuyang12014@gmail.com.
Abstract:
The sensitivity of traditional diffraction grating sensors is limited by the spatial resolution of the measurement setup. Thus, a large space is required to improve sensor performance. Here, we demonstrate a compact hexagonal photonic crystal (PhC) optical sensor with high sensitivity. PhCs are able to diffract optical beams to various angles in azimuthal space. The critical wavelength that satisfies the phase matching or becomes evanescent was used to benchmark the refractive index of a target analyte applied on a PhC sensor. Using a glucose solution as an example, our sensor demonstrated very high sensitivity and a low limit of detection. This shows that the diffraction mechanism of hexagonal photonic crystals can be used for sensors when compact size is a concern.
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