Analysis of Phase Noise in Waveguide-integrated Optical Test Structures in Silicon Photonics

This paper experimentally investigates and interprets the effects of noise and non-linearity in a silicon photonic optical test structure. For the analysis different optoelectronic phase noise measurement techniques are used. Our tests focuses on the performance of integrated optical test structures using femtosecond pulses in the 1550 nm spectral range. A primary objective is to understand the behaviour of silicon photonic waveguides that can be further employed in the implementation of an optoelectronic phase-locked loop (OEPLL) in silicon photonics technology. A comparison of our results, as well as a discussion on the different optoelectronic phase noise measurement techniques are presented. Our findings provide insights that can be leveraged to optimize the design and performance of ultra-low phase noise on-chip OEPLL systems locking to mode-locked laser (MLL) signals. In the future such systems can be essential for advanced communication and sensing applications.