All-polymer photonic bandgap Bragg fibers for bio-chemical sensors and spectrometers

In this talk, we demonstrate bio-chemical fiber-optic sensors and fiber bundle spectrometers based on the hollow- and solid-core all-polymer Bragg fibers fabricated in our group. The hollow-core Bragg fiber sensor operates on a resonant sensing mechanism in which variations in refractive indices of liquid analytes filling the fiber core can be detected by interrogating the resonant wavelength shift in fiber transmission. Experimental sensitivity of the sensor is found to be ~1400nm/RIU which is comparable to that of a SPR sensor. The Bragg fiber bundle spectrometer fabricated with solid-core Bragg fibers can be used to replace traditional spectrometers based on movable gratings, leading to significant cost-saving and increased acquisition speed. As an example of the application of the Bragg fiber bundle spectrometer, we integrate it into the hollow-core Bragg fiber sensing system for spectral acquisition.