High-Speed, Reliable, Self-Adaptive Calibration for Dual MZI-Based Silicon Photonics Switch Applications

This paper introduces a high-speed, reliable, self-adaptive calibration method for dual Mach-Zehnder Interferometer (MZI)-based 8×8 silicon photonic switches. Employing a fully automatic phase-error calibration technique, this method dynamically compensates for phase errors, thereby significantly enhancing the precision and efficiency of the calibration process across process-induced variations. By refining the calibration algorithms and detailing the procedural steps, the method predicts and optimizes phase errors across successive MZIs with remarkable accuracy. The introduction of chipspecific linear regression analysis facilitates this process, achieving calibration precision close to theoretical limits. A prototype was developed to test the approach across different chips, demonstrating its effectiveness. Experimental results demonstrated a sampling efficiency of 3.6 measurement points per switch state, approaching the theoretical limit of 3, with a potential calibration speed of under 20 seconds for the entire polarization-independent 8×8 switch consisting of 256 MZIs. To our knowledge, this is the first demonstration of such a precisionenhancing calibration method, suggesting its practical applicability not only in improving the cost-effectiveness and energy efficiency of silicon photonic technologies but also in enabling applications in high-density optical data transmission and processing systems.