Few-Layer Graphene Heater Enabled High-Precision Phase-Change Photonic Devices

Abstract

Photonic computing overcomes the power and interconnect bottlenecks of conventional electronics through its high bandwidth, low latency, and parallel processing capability, making it ideal for next-generation AI and data-intensive applications. However, current photonic computing devices still face challenges in modulation efficiency, precision, and state retention. Here, we demonstrate a few-layer graphene (FLG) heater enabled high precision nonvolatile photonic device based on Sb₂Se₃ phase-change material. By investigating the modulation mechanism of the FLG heater, we achieve precise control over the phase-change photonic device. Combined with a strip-segmented device structure, 101 highly uniform and distinct optical states are realized. Benefiting from the more efficient modulation of phase-change photonic devices by the FLG heater, a total phase shift of 4.5π is achieved over a 30 μm length of Sb₂Se₃, corresponding to a phase modulation efficiency of 0.15π/μm. This work provides a feasible solution to achieve high precision and high phase modulation efficiency in photonic devices, lays a foundation for more accurate and highly integrated photonic computing systems.