Optimizing electro-optic modulators for interfacing color centers in an integrated silicon carbide platform

Silicon carbide is a promising material platform for hosting various color centers suitable for quantum information processing. Here, we report the design and demonstration of an integrated electro-optic modulator that can directly interface the silicon vacancy centers in the 4H-silicon-carbide-on-insulator platform. Despite a relatively low electro-optic coefficient ($0.22$ pm/V), the optimized silicon carbide modulator is able to work in the 920 nm range with a propagation loss of less than $0.5$ dB/cm, featuring a 3-dB bandwidth around 500 MHz, an extinction ratio of 8-12 dB for an operating peak-to-peak voltage of 10 V, and a footprint of less than $0.1\ \text{mm}^2$. With such modulation performance, our work provides a cost-effective solution for the chip-scale implementation of the electro-optic modulation technology for interfacing color centers in the silicon carbide platform.