Active Trimming of High-Speed SiN Photonic Micro Ring Resonators Using Thin Film Ferroelectrics

Fabrication of photonic devices needs nanometer-scale precision for devices to be in the optimal point of operation. Achieving this precision typically requires complex and costly post-fabrication processes or thermo-optic tuning using resistive heaters. In this work, we demonstrate active trimming of ring resonators on a SiN platform using a ${\text{Pb}\left(\text{Zr,Ti}\right)O}_3$ cladding layer. A DC bias is applied in order to tune an optical modulator in the optimal point of operation while maintaining a constant high-frequency response. This approach is promising for high-speed applications where precise tuning is critical.