Silicon micro-ring resonator modulator for inter/intra-data centre applications

Abstract

The recent and rapid growth of silicon photonics is driven by the ever-increasing demand for bandwidth inside and between data centres. Silicon photonics can offer an unparalleled performance in terms of scalability and power consumption with low-cost fabrication through the leveraging of CMOS fabrication techniques. This thesis describes research on the silicon micro-ring resonator modulator, a device which combines energy-efficiency with a compact footprint that is ideal for data centre applications. Both theoretical and experimental work is described in the context of improving the reachability, capacity and stability of the silicon micro-ring resonator modulator for inter/intra-data centre communication. Chapter 2 presents modeling work using MATLAB® that provides predictive results for both device-level and system-level performance. Chapter 3 studies the chirp characteristic of an over-coupled silicon micro-ring resonator modulator and its capability of generating a negative-chirp modulation. The resulting chirp-induced power penalty is measured to be as low as 2.5 dB after 100 km transmission. Chapter 4 focuses on the advanced modulation techniques that can be efficiently exploited for increasing the spectral efficiency in the typically band-limited system. A record single-polarization 104 Gb/s data rate per wavelength (direct-detect) was achieved by using digital signal processing to alleviate the modulation deficiencies that are specific to the silicon micro-ring resonator modulator. In Chapter 5, a generic resonance control method using intrinsic defect-mediated photocurrent is described and experimentally demonstrated to provide stability for the silicon micro-ring resonator modulator during high-speed operation. This control method can also lead to an “all-silicon” system without the need for power detection using germanium.