Performance Limits of Phase Change Integrated Photonics

Integration of chalcogenide phase-change material (PCM) with photonic circuits offers a practical route of introducing nonvolatile reconfiguration—a long-missing capability in integrated photonics. The prospect has motivated a surge of research efforts in this field and significant improvements in the performance of PCM-based photonic devices. These advances prompt an important question: what are the ultimate performances that can be achieved in PCM-based photonic devices? In this paper, we address this question by quantitatively analyzing their performance bounds on optical loss, crosstalk, energy consumption, and phase-tuning precision. The primary factors constraining the device performances are elucidated, and potential mitigation strategies are also discussed.