Power handling of silicon microring modulators

Area of Science:

• Photonics
• Optical Communications
• Materials Science

Background:

• Silicon photonic wavelength division multiplexing (WDM) transceivers are key for multi-Tbps data rates in short-reach optical interconnects.
• Microring resonators offer low power consumption and small footprints, crucial for scalable WDM systems.
• Silicon's optical nonlinearity can cause performance degradation at milliwatt optical powers in resonant modulators.

Purpose of the Study:

• To develop a theoretical time-domain nonlinear model for optical power dynamics in silicon resonant modulators.
• To investigate the impact of high input optical powers on modulation quality.
• To identify key nonlinear effects and their consequences on system performance.

Main Methods:

• Derivation of a theoretical time-domain nonlinear model.
• Inclusion of two-photon absorption, free-carrier absorption, thermal, and dispersion effects.
• Experimental validation of the model with high optical power inputs.

Main Results:

• The model accurately predicts performance degradation due to nonlinear effects.
• System bistability necessitates precise resonance wavelength initialization.
• An optimal input optical power exists; exceeding it diminishes modulation quality.

Conclusions:

• Nonlinear effects in silicon resonant modulators are critical at high optical powers.
• Understanding bistability and optimal power is essential for designing high-performance silicon photonic WDM systems.
• The developed model provides a valuable tool for analyzing and optimizing these devices.