Silica nanofiber bandgap filters for the multiplexing of high sensitivity photonic crystal cavity sensors array

We proposed a novel design of refractive index (RI) sensor array based on high sensitivity 1D photonic crystal (PC) nanofiber cavity, which can support 7-channel sensing multiplexing at the same time. In order for all sensors to be interrogated simultaneously with a single input/output port, all channels are connected to a 1D-PC filter and then connected in parallel by using a 1×7 power splitter and a 7×1 power combiner in the input port and output port, respectively. The entire sensor array structure is designed on a single mode fiber (SMF) of only 10-μm-diameter. Using 3D-FDTD simulation method, the photonic crystal nanofiber sensor (PCNFS) shows a Q-value of ~10
⁵
, and the average RI sensitivity as high as 663.8 nm/RIU can be obtained. We believe that this kind of highly integrated, high-sensitivity, nanofiber-based sensor array has promising applications in gas sensing and other occasions which require high sensitivity.