Fig. 1. Structure of the PCF sensor. (a) Sectional view; (b) schematic diagram of the stacking manufacturing method

Fig. 2. Schematic diagram of the PCF sensing. (a) Mismatched strand; (b) complementary strand

Fig. 3. Dispersion characteristics and loss characteristics of the core mode, and dispersion characteristics of SPP when n=1.333

Fig. 4. Sensing characteristic diagram. (a) Loss of the refractive index of different solutions; (b) relationship between resonance wavelength and refractive index of solution to be tested

Fig. 5. Effect of Au film thickness on sensing characteristics. (a) Loss curve of core guided mode; (b) variation curve of resonance wavelength with refractive index of the solution to be measured

Fig. 6. Effect of duty cycle on sensing characteristics. (a) Loss curve of core guided mode; (b) variation curve of resonance wavelength with refractive index of the solution to be measured

Fig. 7. Effect of hole diameter on sensing characteristics. (a) Loss curve of core guided mode; (b) variation curve of resonance wavelength with refractive index of the solution to be measured