Self-calibrating microring synapse with dual-wavelength synchronization

As a resonator-based optical hardware in analog optical computing, a microring synapse can be straightforwardly configured to simulate the connection weights between neurons, but it faces challenges in precision and stability due to cross talk and environmental perturbations. Here, we propose and demonstrate a self-calibration scheme with dual-wavelength synchronization to monitor and calibrate the synaptic weights without interrupting the computation tasks. We design and fabricate an integrated 4 x 4 microring synapse and deploy our self-calibration scheme to validate its effectiveness. The precision and robustness are evaluated in the experiments with favorable performance, achieving 2-bit precision improvement and excellent robustness to environmental temperature fluc-tuations (the weights can be corrected within 1 s after temperature changes 0.5 & DEG;C). Moreover, we demonstrate matrix inversion tasks based on Newton iterations beyond 7-bit precision using this microring synapse. Our scheme provides an accurate and real-time weight calibration independently parallel from computations and opens up new perspectives for precision boost solutions to large-scale analog optical computing.& COPY; 2023 Chinese Laser Press

Automated summary

In this study, a self-calibration scheme with dual-wavelength synchronization is proposed and demonstrated to monitor and calibrate the weights of a microring synapse. The scheme successfully addresses the challenges of precision and stability caused by cross talk and environmental perturbations. The experiments show that the scheme achieves favorable performance, with a 2-bit precision improvement and excellent robustness to environmental temperature fluctuations. Moreover, matrix inversion tasks beyond 7-bit precision are demonstrated using this microring synapse, opening up new perspectives for precision boost solutions in large-scale analog optical computing.