Fig. 1. Structure diagram. (a) Electromagnetic sensing structure based on two-dimensional photonic crystal with symmetrical nanocavities; (b) structure of locally amplified H0 cavity; (c) structure of locally amplified improved H1 cavity

Fig. 2. Transmission spectrum of symmetrical side cavity coupled electromagnetic sensing structure based on two-dimensional photonic crystal

Fig. 3. Variation of λr, S_n, and Q with d₀. (a) Symmetrical H0 cavity structure; (b) unilateral H0 cavity structure; (c) symmetrical H0 cavity structure; (d) unilateral H0 cavity structure

Fig. 4. Reflection spectra under different voltage conditions with fixed magnetic field strength. (a) 14-32 V; (b) 32-50 V

Fig. 5. Relationship between wavelength and voltage. (a) 14-32 V; (b) 32-50 V

Fig. 6. Results when magnetic field changes. (a) Reflection spectra under different magnetic field strength conditions with fixed voltage; (b) relationship between wavelength and magnetic field strength