Fig. 1. Structure of thin-film lithium niobate MZI electro-optic modulator with spoof surface plasmon polariton electrodes. (a)Structure of MZI electro-optic modulator with metal photonic crystal electrodes; (b)longitudinal section structure of MZI electro-optic modulator; (c) cross-section structure of MZI electro-optic modulator

Fig. 2. Electromagnetic characteristics of slow light effect thin-film lithium niobate electro-optic modulators. (a) Variation of optical loss with the gap of electrodes;(b) eigenmode field distributions of microwave mode TE₀ with a eigenfrequency of 220 GHz and light wave mode TE₀₀ with a frequency of 193.5 THz (as shown in the inset); (c) dispersion curve of light wave mode TE₀₀ of lithium niobate electro-optic modulators; (d) dispersion curves of microwave modes TE₀ and TE₁ of lithium niobate electro-optic modulators; (e) longitudinal section of microwave eigenmodes field distributions TE₀ and TE₁of_{metal photonic crystal unit}

Fig. 3. Analysis of modulation effect of the slow light effect electro-optic modulators. (a) Dispersion curves of microwave modes with single parameter dchanging; (b) variation of group velocity v_g of microwave with parameter d at the same frequency 220 GHz ; (c) variation of electro-optic overlap surface integration factor with the propagation direction y of different parameter d of periodic structure unit; (d) variation of electro-optic overlap volume integration factor with parameter dat the same frequency 220 GHz