The exponential growth in Data Centre (DC) and Access Network traffic over the past decade has been fuelled by new services and applications being employed by residential and business users. However, the energy consumption of these networks is now becoming a focus of attention as one global challenge (improved broadband connectivity for all) seemingly has a negative effect on another (climate change). It is thus imperative to develop new energy efficient optical technologies which can significantly reduce the energy consumption of future optical networks. This project will combine semiconductor physics and device design, with optical communication & photonics system expertise, to develop energy efficient, high-capacity transmission and switching systems for use in future DC and access networks.
To overcome the challenges associated with increasing data rates in optical access and data centre networks there is a move towards external modulation of single mode lasers. This enables longer transmission distances due to the reduced frequency chirping associated with external modulation, and provides a future proof roadmap towards Tbps systems employing Wavelength Division Multiplexing (WDM) technology. The implementation of WDM technology and optical switching can significantly reduce energy consumption in future optical networks. The single mode lasers employed in these systems need to operate at high power levels (> 13dBm) to overcome the losses associated with the external modulation process and provide sufficient margin in the transmission link, and typically each wavelength channel will require a separate laser source with a temperature controller to ensure stable operation. This project will explore the use of optical frequency combs in future energy efficient optical networks for both data centre and optical access systems.