Photonic crystal fiber sensor

A sensor for sensing an analyte, the sensor comprising:

• a tunable light source configured to provide a substantially single optical mode of light;
• a detector;
• a processor;
• and
• a resonator configured to resonate light of a predefined frequency, the resonator comprising a coil, the coil comprising a photonic crystal fiber, the photonic crystal fiber comprising:
• a solid region configured to guide a substantially single optical mode of light, the substantially single optical mode of light passing through the coil multiple times;
• and
• a cladding surrounding an exterior of the solid region, the cladding comprising at least one hollow channel configured to receive a fluid from an external source, the fluid may contain more than a measurable quantity of an analyte, a portion of the single optical mode of light extends into the at least one hollow channel configured to receive a fluid,
• wherein the tunable light source is in optical communication with the detector and the resonator, the resonator is in optical communication with the detector, and the detector is in one of electrical or optical communication with the processor, and wherein the detector detects a resonance signal centered at the resonance frequency as the tunable light source is tuned through a region about the resonance frequency, a predetermined change in the resonance signal detected by the detector indicates the quantity of the analyte in the fluid.