WGM Micro-Fluidic-Channel Based on Reflection Type Fiber-Tip-Coupled Hollow-Core PCFs

A micro-fluidic-channel is proposed based on a fiber-tip-excited hollow-core photonic crystal fiber microresonator. The reflection conical fiber tip is fabricated based on electric arc fusion technique. A quality factor up to $8.65 \times 10^{\mathrm { {4}}}$ has been experimentally acquired at $\sim 1557.75$ nm. Theoretical simulation results indicate that the refractive index sensitivity of the whispering-gallery-mode resonance wavelength reaches 1259.9211 nm/RIU for biocompatible low refractive index range. The proposed microfluidic detection platform has a few desirable merits, such as ease of fabrication, low-cost, and structure robustness, which ensures its applicability for practical use in chemical as well as biological sensing applications.