Topological edge states electro-optic modulator based on valley photonic crystals

Topological photonic devices provide robust transmission of optical signals. This work proposes a topological modulator scheme, which constructs valley photonic crystals on a silicon slab. Mach-Zehnder (MZ) structure is formed by the valley edge states, and based on the carrier dispersion effects, electro-optic modulation is achieved. The device size is only 18.59 × 47.1 μm. Theoretical analysis and simulation results show that the half-wave voltage length product can reach 0.0201 V ∙ cm. Compared to traditional silicon MZ modulators, it greatly reduces size and improves modulation efficiency.