A Computationally Efficient Integrated Coupled Opto-Electronic Oscillator Model

Abstract

Coupled opto-electronic oscillators can generate microwave signals with very low phase noise. Several approaches for modelling these oscillators exist, but none of them include the fast carrier dynamics of the mode-locked laser, due to computational limitations. In this work, we present a new model, that is based on a computationally efficient model for semiconductor mode-locked lasers, which is capable of simulating both the fast laser dynamics and the long term phase stability. We use it to model the phase noise of a hybridly integrated coupled opto-electronic oscillator. The results show that a timing jitter of down to $\mathbf {\sim} \text{0.2}$ $\text{ps}$ in the integration range from $\text{10}$ $\text{kHz}$ to $\text{10}$ $\text{MHz}$ is achievable when using an integrated delay line of $\text{10.2}$ $\text{m}$ in the opto-electronic feedback path. It is also shown that by increasing both gain and bandwidth of the opto-electronic feedback link, the timing jitter is reduced. Together, these results present a path towards low phase noise performance of hybridly integrated coupled opto-electronic oscillators, and the model serves as a new design tool. Such oscillators might increase, for example, the spectral efficiency in future data communication systems and thus enable higher data rates.