Ultrasensitive refractive index sensor based on graphene coated hollow core fiber

摘要

A high-quality nanolayer graphene (NLG) coated hollow core fiber (HCF) platform has been demonstrated for accurate monitoring of refractive index (RI) changes so far mainly operate in liquids but not in air. The NLG with high index is deposited on the outer surface of the HCF, and an enhanced anti-resonant reflecting guidance is formed, which induces sharp periodic lossy dips in the transmission spectrum. A cute experiment conducted interrogating the transmission intensity of the lossy dip demonstrates a high resolution of 2.73×10^-6 RIU and a sensitivity of -365.9 dB/RIU, which is two or three times higher than that of intensity-modulated RI sensors reported previously. We believe that this configuration opens research directions for highly sensitive sensing in researches of chemistry, medicine, and biology.