NEO-PGA: Nonvolatile electro-optically programmable gate array.

Abstract

Programmable photonic integrated circuits promise reconfigurable, multifunctional photonic systems, analogous to electronic field programmable gate arrays. However, their scalability is constrained by reliance on volatile thermo-optic tuning, which incurs high power consumption, large footprints, and thermal cross-talk. Chalcogenide phase-change materials (PCMs) offer a superior alternative because of their nonvolatility and substantial optical contrast, yet challenges such as optical loss and bit precision have severely hindered their large-scale adoption. Here, we demonstrate low-loss, multibit control of the PCM Sb₂Se₃ using a closed-loop "program-and-verify" approach. We integrate electrically reconfigurable PCM gates into 300-millimeter silicon photonic platforms, implementing both circulating and forward Mach-Zehnder interferometer meshes. The circulating mesh enables broadband switching fabrics and high-<i>Q</i> coupled resonators with unprecedented local control of coupling rates, while the forward mesh supports spatial mode sorting. These results establish a scalable, nonvolatile photonic programmable gate array enabled by PCMs, opening pathways to general-purpose, on-chip programmable photonic systems.