Fig. 1. Two-dimensional simulation model of gold grating-insulator-gold film

Fig. 2. Reflection spectra of resonator under different incident light. (a) TE light incident; (b) TM light incidence

Fig. 3. Reflection spectra of TM light incident at different dielectric layer thicknesses. (a) 30 nm; (b) 600 nm

Fig. 4. Distribution of Y-direction electric field components under different resonance modes. (a) 1^st order TM₀ resonance mode, λ=1671.69 nm; (b) 2^nd order TM₀ resonance mode, λ=985.84 nm; (c) 3^rd order TM₀ resonance mode, λ=795.22 nm; (d) Bloch surface mode, λ=1300.38 nm

Fig. 5. Distribution of X-direction electric field component in case of F-P resonance mode with TM light incident and t=600 nm. (a) 1^st order F-P resonance mode, λ=1868.91 nm; (b) 2^nd order F-P resonance mode, λ=957.16 nm

Fig. 6. Resonance diagram of TM₀ mode

Fig. 7. Symmetric metal-coated dielectric waveguide model

Fig. 8. Performance of MIM structure with cavity length t=70 nm. (a) Reflection spectrum chromatics at different grating widths W; (b) variation curve of effective refractive index of TM₀ resonant mode with wavelength

Fig. 9. Performance of MIM structure under different refractive index of intermediate dielectric layer. (a) Reflection spectrum chromatics; (b) variation curve of effective refractive index of TM₀ resonant mode with wavelength

Fig. 10. Reflection spectrum chromatics and Y-direction electric field component at resonant wavelength under different grating thicknesses t_g. (a) Reflection spectrum chromatics under different grating thicknesses t_g; (b) t_g=20 nm, Y-direction electric field component at resonance wavelength; (c) t_g=200 nm, Y-direction electric field component at resonance wavelength

Fig. 11. Reflection spectrum and Y-direction electric field component at resonant wavelength under different grating periods P. (a) Reflection spectrum chromatics under different grating periods P; (b) P=900 nm, Y-direction electric field component at resonance wavelength; (c) P=1200 nm, Y-direction electric field component at resonance wavelength

Fig. 12. Reflection spectrum chromatics and Y-direction electric field component at resonant wavelength under different gold film reflector thicknesses t_m. (a) Reflection spectrum chromatics under different gold film reflector thicknesses t_m; (b) t_m=20 nm, Y-direction electric field component at resonance wavelength; (c) t_m=200 nm, Y-direction electric field component at resonance wavelength

Fig. 13. Performance curves of resonant wavelength and effective refractive index of nano-resonator under different conditions. (a) After refractive index of medium in cavity is fixed, resonant wavelength of nano-resonator varies with length of the cavity; (b) refractive index n of medium in cavity is 1.4, and effective refractive index of nano-resonator with different cavity lengths; (c) after cavity length is fixed, resonant wavelength of nano-resonator varies with refractive index; (d) cavity length t=50 nm, effective refractive index of nano-resonator under different refractive index

Fig. 14. SEM images under different magnification of fiber end grating . (a) 2000×; (b) 10000×

Fig. 15. Assembly system diagram and F-P resonant interference spectrum. (a) Five-dimensional displacement control platform, CCDs in horizontal and vertical planes; (b) optical fiber clamp and gold mirror platform; (c) position relative position of optical fiber and gold mirror observed by CCD; (d) F-P resonant interference spectra at different distances

Fig. 16. Assembly flowchart of optical fiber end nano-resonant structure

Table 1. Response sensitivity of nano-resonator to cavity length variation with fixed refractive index of medium in cavity

Table 2. Response sensitivity of resonator with different cavity length to refractive index change of medium in cavity