Heterogeneously integrated micro-ring with SnS₂ for dual-functional optical modulation and photodetection

Achieving simultaneous optical modulation and photodetection in a single device represents a key objective for advancing integrated photonics. However, fabricating such dual-functional devices remains challenging due to process complexity, material instability, and weak light–matter interaction. This work demonstrates a dual-functional device through the heterogeneous integration of few-layer SnS₂ onto a silicon-on-insulator (SOI) microring resonator. Using an electrode-engineered design that eliminates the need for external gate control or heterojunctions, the device achieves simultaneous light modulation and detection. This design not only simplifies fabrication but also maintains independent control ports, enabling real-time monitoring of the optical modulation state and paving the way for integrated feedback in on-chip photonic computing systems. The modulator achieves a modulation depth of 23 dB, while the photodetector shows a responsivity of 0.38 A/W at −2 V through a hot-carrier-assisted mechanism. This work provides a compact and versatile platform for multifunctional photonic integration, supporting the development of more efficient and reliable on-chip photonic computing.