On-chip reconfigurable analog optical computing 4f system based on phase-change materials

Analog optical computing has garnered significant attention owing to its ultra-high speed, ultra-low power consumption, and parallel processing capabilities. Recent advances in Fourier optics and metasurface technology have enabled the realization of on-chip optical differentiators, integrators, and differential equation solvers. However, conventional devices are constrained to a single function once fabricated, lacking dynamic reconfigurability. In this study, we propose an on-chip reconfigurable analog optical computing device based on a silicon-on-insulator platform. The design employs a modified 4f system, where the air-slit structure in the computational metasurface is replaced with phase-change material (Ge₂Sb₂Te₅ and Sb₂S₃) array blocks. By independently controlling the phase transition of each block, we demonstrate dynamic switching between differentiation, integration, ordinary differential equation solving, and integro-differential equation (IDE) solving within a fixed structure. The IDE solving is first implemented on-chip. Theoretically, this device can be reconfigured for arbitrary computational operations. Our approach offers a promising solution for the large-scale integration of optical computing chips, with potential applications in high-speed, complex computations for artificial intelligence.