Enhanced Linearity Dual-Drive Mach-Zehnder Modulator Assisted by Micro-Ring Resonator on SOI Platform

We propose in this paper a highly linear dual-drive silicon-on-insulator Mach-Zehnder modulator (MZM) assisted by a micro-ring resonator for the microwave photonics and the integrated optical gyroscope applications. By optimizing the DC biases on both the micro-ring and the MZM arm, as well as the coupling efficiency between them, the modulator’s output can be maximally tuned. At specific operating points, third-order intermodulation distortion (IMD3) is suppressed, enabling a linearized transfer function. Simulations demonstrate a spurious-free dynamic range (SFDR) of up to 142.3 dB·Hz^2/3—a significant improvement over conventional dual-drive MZMs. Simulation results reveal that the modulator schematic we proposed is insensitive to the fab process as the SFDR can be optimized with the bias voltages after fabrication. This work provides a viable path toward high-performance modulators for high-density photonic-electronic integration.